O-Word Vocabulary Definitions
| oakum. | hemp or jute fiber with tar, creosote, or asphalt, for caulking ships, pipes |
| oak will. | oak tree disease |
| oarfish. | 30 feet long |
| oast. | kiln: hops, malt, tobacco |
| obligato. | not to be left out |
| obcordate. | heart-shaped, attached at bottom of heart |
| obesh. | West Indies voodoo |
| obelia. | marine hydroids |
| obelus. | mark (— or )used in ancient manuscripts to show doubtful or spurious |
| obi. | wide sash worn by Japanese women |
| Obie. | Off-Broadway award |
| obiter dictum. | side remark (opinion voiced by judge that has only incidental bearing) |
| objective complement. | "They elected him governor") Noun complements the verb |
| objective correlative. | situation that objectifies an emotion to elicit a response from reader |
| objectivism. | reality is real; objective themes in art |
| objet trouvé. | a found object |
| objurgate. | to sharply rebuke, berate |
| oblanceolate. | broader and rounded at the apex and tapering at the base, e. g., leaf |
| oblast. | USSR: administrative division within a republic |
| oblate. | layman dedicated to religious life; member of religious community |
| oblation. | offering; offering of bread and wine; charitable offering or gift |
| obligar. | one who binds himself by legal contract |
| obovate. | egg-shaped, with narrow end attached to stalk |
| obscurant. | one who deliberately opposes intellectual advancement and reform; characteristic of an adolescent |
| obscurantism. | deliberately withholding news from the public; an art style |
| obsequy | funeral rite |
| obtest. | supplicate, entreat, adjure, |
| obtund. | to make less intense, dull (hebetate?) |
| obturator. | one that closes or obstructs; something that closes an opening in the body; a prosthetic device serving the same purpose |
| obvert. | to present another side; to alter the appearance of |
| occipital bone. | curved, trapezoidal, compound bone that forms the lower back of the skull |
| occiput. | back of skull (occipital area) |
| occlusal. | of or pertaining to occlusions of the teeth |
| oceanid. | any of the daughters of Oceanus and Tethys |
| ocellus. | small simple eye found in many invertebrates; an eye-like marking |
| ochlocracy. | mob rule |
| ochlophobia. | demophobia (fear of crowds) |
| ocotillo. | a cactus-like Mexican tree |
| ocrea. | sheath of stipules enclosing the leafstalks of certain plants |
| octandrious. | Having 8 stamens |
| octenniel. | every 8 years |
| octavo. | page size, 5" X 8" to 6" X 9.5" of a book composed of printer's sheets folded into 8 leaves, originally printed on one side of each page |
| octodecimo. | 4" X 6.5", 18 leaves or 36 pages. |
| octoploid. | having 8 haploid sets of chromosomes |
| octoroon. | 1/8th African |
| octrol. | a local tax levied on certain items brought into European countries |
| odalisque. | a female slave or concubine in a harem |
| odd-pinnate | pinnate, with a single unpaired leaflet at the end of the leafstalk |
| odeum. | a small Greek/Roman building for public performances of music and poetry; a contemporary theater or concert hall |
| odograph. | records speed and distance traveled |
| odonate. | dragonflies and damselflies: two pairs of membranous wings, large eyes |
| odontoblast. | tooth cell in surface of dental pulp that produces dentine |
| odontoid. | resembles a tooth |
| odontoid process. | small tooth-like projection from second vertebra of neck around which the first vertebra rotates |
| odontology. | anatomy, growth, and diseases of the tooth |
| odontophore. | a protrusile structure at the base of the mouth of most mollusks, supporting the radula |
| oenology. | the study of wines |
| oenomel. | beverage of ancient Greece consisting of wine and honey |
| oeuvre. | the sum of an artist's life work |
| ofay. | a honky |
| offal. | rubbish |
| officient. | one who officiates at a religious service; celebrant |
| officiary. | body of officials or officers; an official; having a title (used of a dignitary) |
| officinal. | a drug available with a prescription; medical plant |
| offing. | that part of the sea that is distant yet seen from the shore |
| off-putting. | tending to disconcert or repel |
| off-scouring. | something that is scoured off: a social misfit or outcast |
| ogee. | curve or molding like integral sign; arch of two curves meeting at a point |
| ogham. | 6th C. Irish writing alphabet |
| ogive. | diagonal rib of Gothic arch; a pointed arch; cumulative frequency distr. |
| Oglala. | Teton Dakota group |
| ogress. | a lady ogre |
| oidium. | thin-walled fungal spore |
| okapi. | like a giraffe but short neck and smaller |
| old-man-and-woman. | house leek |
| old--man cactus. | tree-like cactus with tufts of long white hair on branch tips |
| old-man's-beard. | Spanish moss and virgin's bower |
| oleander. | poisonous evergreen shrub |
| oleaster. | fragrant small Eurasian tree with silvery-green leaves and olive-like fruit |
| oleograph. | chromolithograph imitating an oil painting; lace-like oil patterns on water |
| oleum. | sulfer trioxide in sulfuric acid (corrosive) |
| oligochaete. | earthworms, et al |
| oligoclase. | plagioclase |
| oligocythemia. | cellular blood deficiency, causing anemia |
| oligogene. | gene that determines major qualitative hereditary characteristics |
| oligomer. | polymer consisting of two, three, or four monomers |
| oligophagous. | feeding on a limited variety of foods |
| oligophrenia. | mental deficiency |
| oligopoly.. | too few sellers |
| oligopsony. | too few buyers |
| oligotropic. | lacking in plant nutrients, with an abundance of dissolved oxygen (lake) |
| oli. | heavily spiced stew; medley; musical medley; burlesque entracte |
| olivary. | shaped like an olive' oval bodies on either side of the medulla oblongata |
| olivenite. | copper arsenate |
| olivine. | iron and Mg silicate, used as refractory and in cements |
| olla podidra. | highly seasoned meat and vegetable stew; assorted mixture (olio?) |
| Olympiad. | the 4 years between Olympics; celebration of modern Olympic Games |
| omasum. | the third stomach of a ruminant (as compared to abomasum) |
| ombre. | 40-card card game |
| ommatidium. | one eye element in a bug's eye |
| omatophore. | movable stalk with eye (snails) |
| omnium gatherum. | hodge-podge |
| omphalos. | navel; central part, focal point |
| onager. | wild ass; medieval stone-propelling siege engine |
| onanism. | masturbation; coitus interruptus; self-gratification |
| oneiric. | pertaining to dreams |
| oneiromancy | divination by dreams |
| onomastics. | study of specialized vocabularies; system underlying formation of words |
| oocyst. | encysted form of some sporozoan zygotes |
| oocyte. | a cell, derived from an organism, that undergoes mitosis, produces ovum |
| oogamete. | female gamete of protozoons (gamete: sperm or egg cell) |
| oogamous. | small sperms and larger ova |
| oogamy. | fertilization of oogamous gametes |
| oogenesis. | enlargement and meiosis of an oogonium that produces an ovum |
| oogonium. | one of the cells that form the bulk of ovarian tissue |
| oolite. | small, round, calcareous grain in limestone; limestone composed of oolites |
| oology. | branch of ornithology dealing with bird's eggs |
| oolong. | partly-fermented dark Chinese tea |
| oophoritis | ovarian inflammation |
| oophyte. | stage in plants undergoing metagenesis during which sexual organs appear |
| oosperm. | a fertilized egg |
| oosphere. | a female gamete ready for fertilization |
| oospore. | thick-walled spore |
| ootheca. | egg case of certain insects and mollusks |
| ootid. | one of the four sections into which a mature ovum divides |
| opacifier. | chemical additive making it opaque |
| opah. | large, vividly-colored fish. Edible |
| op-ed page. | personal opinions page |
| opera bouffe. | comic, often satiric, opera |
| opera comique. | has spoken, as well as sung dialogue |
| operculum. | lid like gill flap or horny shell cover in snails; flap like the layer of tissue over an erupting tooth |
| operon. | cluster of proximate genes churning out related enzymes under control of remote gene |
| operose. | involving great labor; laborious; industrious |
| ophidian. | relating to snakes |
| ophidiology. | study of snakes |
| ophite. | green rocks such as diabase, serpentine |
| Ophiuchus. | equatorial constellation |
| opthalmia. | inflammation, especially conjunctivitis |
| opisthobranch. | gills, little or no shell, two pairs of tentacles |
| opisthoganous. | receding jaws |
| opsin. | protein constituent of rhodopsin |
| opsonin. | substance in blood that makes bacteria susceptible to phagocytosis |
| optative. | expressing a wish; optative mood |
| optic chiasma. | partial decussation of optic nerve fibers on bottom of hypothalamus |
| opuntia. | cactus |
| opuscule. | a minor opus |
| oquassa. | freshwater fish |
| orach. | like spinach |
| oratory. | place for prayer, like a private chapel |
| orc. | killer whale |
| orchidaceous. | characteristic of orchids; suggesting ostentatious luxury, showy |
| orchil. | lichen yielding dye |
| orchis. | orchids: magenta, white, or magenta-and-white |
| Orcus. | Hades; Pluto |
| ordo. | annual calendar with instructions for Mass and office for each day |
| ordonnance. | arrangement of elements in a literary or artistic composition or an architectural plan |
| oread. | a mountain nymph |
| oreide. | oroide |
| Orestes. | son of Agamamnon and Clymenestra who, his sister, Electra, avenged his father by slaying his mother and Aegisthus |
| organdy. | transparent, crisp fabric used for trim, curtains, & light apparel |
| organelle. | a specialized part of a cell that acts like an organ |
| organ of Corti. | specialized structure located on the inner surface of the basilar membrane of the cochlea that contains the sensory receptors that respond to sound |
| organoleptic. | perceived by a sensory organ. |
| organon. | set of principals or methods used in scientific research |
| organotropism | attraction of certain chemicals or microorganisms to certain organs of the body |
| organum. | types of polyphonic music from 9th to 13th C's. |
| organza. | sheer, stiff fabric used for trimming or evening dresses |
| organzine. | a raw-silk thread, usually a warp thread |
| orgeat. | sweet orange and almond used in cocktails and food |
| oribi. | small African antelope |
| oriel. | projecting bay window supported with corbel or bracket. |
| oriflamme. | inspiring standard or symbol; orange-red flag of the Abbey of St. Denis, used as standard by the early kings of France |
| origami. | paper-folding |
| orison. | prayer |
| orlop. | lowest deck of a ship, especially a warship |
| ormer. | an abalone shell |
| orlulu. | oroide; used to decorate furniture, moldings, etc. |
| ornithosis. | like psittacosis. infecting domestic fowl, transmissible to man |
| orogeny. | mountain-building by folding and faulting of the earth's crust |
| orography. | study of physical properties of mountains |
| orology. | study of mountains |
| orotund. | sonorous |
| oroide. | fake gold used in imitation-gold jewelry |
| Orphic. | mystical or occult; capable of casting a charm or spell; ideas set forth in Orpheus' poems |
| Orphism. | ancient Greek mystery religion arising in 6th C. B. C. from a synthesis of pre-Hellenic beliefs with the Thracian cult of Zagreus and soon becoming entangled with the Eleusinian mysteries and the doctrines of Pythgoras |
| orphry. | band of elaborate embroidery on front of ecclesiastical garments; elaborate embroidery, especially when made of gold |
| orpiment. | arsenic trisulfide used in tanning and in linoleum manufacture |
| orpine. | plant |
| Orpington. | chicken |
| orris. | Iris with fragrant rootstock |
| orris root. | guess! Used in perfumery |
| ort. | a small scrap of food; a scrap, a bit |
| orthocephalic. | skull height/skull length = 0.7 to 0.75 |
| orthoclase. | feldspar |
| orthoclastic. | having right-angled cleavage |
| orthoepy. | 1. The study of the pronunciation of words; 2. Customary pronunciations |
| orthogenesis. | the theory that evolutionary change is predetermined by the constitution of germ plasm and is independent of external factors;. The theory that all cultures pass through sequential periods in the same order. |
| orthognathous. | having upper and lower jaws the same length |
| orthomolecular. | theory that mental illness is chemical |
| orthopedics. | surgical or manipulative treatment of skeletal disorders |
| orthopsychiatry. | treatment of incipient and borderline mental disorders, esp., their development in the young |
| orthoopteran. | membranous folded hind wings covered by leathery forewings: locusts, roaches, crickets, and grasshoppers |
| orthorhombic. | three mutually perpendicular axes of different lengths |
| orthoscope. | examines eye through a layer of water compensating for curvature of cornea |
| orthoscopic. | giving undistorted vision |
| orthotropous. | growing straight, so that the micropyle is opposite the stalk |
| orthostichous. | characterized by parallel arrangement in a vertical row |
| orthotics. | branch of medicine that uses prosthetics to support weakened limbs |
| orthotropic. | growing along a vertical axis |
| ortolan. | small, brownish bird eaten as a delicacy (like beccafico); bobolink and sora |
| os. | mouth or opening like a mouth |
| os. | a bone |
| os. | an esker |
| oscine. | passerine birds that include most songbirds |
| oscitancy. | yawning; drowsy or inattentive |
| osculant. | intermediate between two taxonomic groups; closely adhering, embracing |
| osculate. | osculant |
| osculation. | kiss; point where two branches of a curve share, follow a common tangent |
| osculum. | opening in sponge for expelling water |
| osier. | willows with rod-like twigs used in basketry |
| Osiris. | annual death and resurrection personified nature |
| osmic. | osmium compound |
| osmometer. | measures osmotic pressure |
| osmunda. | fern roots used for potting |
| osnaburg. | grain-sack, upholstery, diaper cotton fabric |
| ossein. | gelatinous bone residue used for gelatin and glue |
| ossa. | plural of os |
| ossia. | direction to performer to designate an alternative passage |
| Ossian. | legendary 3rd century Gaelic hero and bard |
| ossicle. | small bone, especially of the inner ear (incus, malleus, ans stapes) |
| ossifrage. | lammergeier; osprey |
| osso buco. | braised veal shanks in white wine |
| ossuary. | container for holding the bones of the dead |
| osteal. | bone or skeleton |
| osteitis. | bone inflammation |
| ostensorium. | a monstrance (receptacle for Eucharist) |
| ostioctasis. | surgical fracture of a bone to reset it. |
| osteoclast. | an instrument used in osteooctasis; a large, multinuclear cell that resorbs bony tissue in osteoclsis |
| osteoid. | resembling bone |
| osteoma. | benign bony tumor, especially in skull |
| osteomalacia. | softening of skull because of calcium deficiency |
| osteomyelitis. | inflammation of bone marrow |
| osteophyte. | small abnormal bone growth |
| ostiary. | one who is ordained in the lowest minor orders; a church doorkeeper |
| ostinato. | short melody or phrase that is constantly repeated in the same pitch |
| ostiole. | a small opening or pore |
| ostium. | same thing |
| ostracod. | minute freshwater crustaceans with bivalve carapace |
| Ostragoth. | 493 to 555 |
| otic. | pertaining to the ear, auricular |
| otiose. | lazy; useless; ineffective, futile |
| otitis. | ear inflammation |
| otocyst. | auditory capsule in an embryo |
| otorhinolaryngology. | ear, nose, and throat specialist |
| ottava. | octave higher than indicated |
| ottavarima. | stanza with eight 11-syllable lines in iambic pentameter. Rhyme scheme: abababcc |
| ottoman. | low sofa or cushioned footstool; heavy rayon fabric with corded texture |
| ouabain. | used for poison darts in Africa |
| oubliette. | dungeon with trap door in ceiling as only exit |
| out-and-outer. | person who goes to extremes |
| outface. | stare down, overcome with self-assured look |
| outfall. | drain discharge |
| outlier. | house lies far from place of business; outlying rock |
| outtake. | film scene dropped in final version |
| outturn. | output |
| outwork. | fortification beyond main defensive position |
| ouzel. | European bird; water ouzel |
| ouzo. | aniseed-flavored Greek liqueur |
| overage. | surplus |
| overblow. | blow a wind instrument to produce an overtone instead of the fundamental |
| overdominance. | heterozygote has phenotype that is better adapted than either homozygote |
| overlie. | to kill by lying upon |
| overshot. | upper part protruding beyond the lower; overshot water wheel |
| ovine. | pertaining to sheep |
| ovipositor. | tubular structure with which insects lay eggs |
| ovisac. | ootheca or Graafian follicle |
| ovoto. | rounded convex molding (quarter-round) |
| ovonic. | Ovshinsky effect |
| ovoviviparous. | eggs hatch within females body |
| Ovshinsky effect. | glossy film switches from nonconductor to semi-conductor upon application of a minimum voltage |
| ovule. | immature ovum; minute structure which, after fertilization, becomes a plant seed |
| oxalia. | flowers |
| oxbow. | ox yoke; bend in river; land enclosed by an oxbow |
| ox-eye. | daisy-like plants; round or oval dormer window |
| oxidative phosphorylation. | intracellular respiration within mitochondria, forming ATP |
| oxlip. | Eurasian primrose |
| oxpecker. | African birds that feed upon ticks on hides of large animals |
| oxycephaly. | congenital. Skull assumes a conical shape. |
| oxytocic. | induces childbirth |
| oxytone. | stress or acute accent on last syllable |
| oxyuriasis. | pinworm infestation |
| eyer and terminer. | hearing and trial; high criminal court in some states |
| oyster-catcher. | black-and-white shore birds with long orange-red bills |
| oyster crab. | lives inside oyster shells |
| oysters Rockefeller. | spinach and cream sauce |
| ozocerite.. | yellow-brown, black, or green hydrocarbon wax used in making electrical insulators, lubricants, and inks |
| ozonide.. | various, often explosive, chemicals created by attaching ozone to an unsaturated compound. Used to locate such bonds |
| ozonize.. | impregnate with ozone. Create ozone. |