| Words | Parts of Speech | Meaning/Definition/Similar Words |
|---|---|---|
| orangetawny | adjective & noun | Deep orange-yellow; dark yellow. |
| orbiculated | adjective | Made, or being, in the form of an orb; having a circular, or nearly circular, or a spheroidal, outline. |
| orbitolites | noun | A genus of living Foraminifera, forming broad, thin, circular disks, containing numerous small chambers. |
| orbitonasal | adjective | Of or pertaining to the orbit and the nose; as, the orbitonasal, or ophthalmic, nerve. |
| orchestrion | noun | A large music box imitating a variety of orchestral instruments. |
| orchidology | noun | The branch of botany which treats of orchids. |
| orderliness | noun | The state or quality of being orderly. |
| oreographic | adjective | Of or pertaining to oreography. |
| organically | adverb | In an organic manner; by means of organs or with reference to organic functions; hence, fundamentally. |
| organizable | adjective | Capable of being organized; esp. (Biol.), capable of being formed into living tissue; as, organizable matter. |
| organogenic | adjective | Of or pertaining to organogenesis. |
| organophyly | noun | The tribal history of organs, — a branch of morphophyly. |
| organoscopy | noun | Phrenology. |
| orientalism | noun | Any system, doctrine, custom, expression, etc., peculiar to Oriental people., Knowledge or use of Oriental languages, history, literature, etc. |
| orientalist | noun | An inhabitant of the Eastern parts of the world; an Oriental., One versed in Eastern languages, literature, etc.; as, the Paris Congress of Orientalists. |
| orientality | noun | The quality or state of being oriental or eastern. |
| orientalize | verb t. | to render Oriental; to cause to conform to Oriental manners or conditions. |
| orientating | present participle & vb. noun | of Orientate |
| orientation | noun | The act or process of orientating; determination of the points of the compass, or the east point, in taking bearings., The tendency of a revolving body, when suspended in a certain way, to bring the axis of rotation into parallelism with the earth’s axis., An aspect or fronting to the east; especially (Arch.), the placing of a church so that the chancel, containing the altar toward which the congregation fronts in worship, will be on the east end., Fig.: A return to first principles; an orderly arrangement. |
| originalist | noun | One who is original. |
| originality | noun | The quality or state of being original. |
| originating | present participle & vb. noun | of Originate |
| origination | noun | The act or process of bringing or coming into existence; first production., Mode of production, or bringing into being. |
| originative | adjective | Having power, or tending, to originate, or bring into existence; originating. |
| ornamenting | present participle & vb. noun | of Ornament |
| ornitholite | noun | The fossil remains of a bird., A stone of various colors bearing the figures of birds. |
| ornithology | noun | That branch of zoology which treats of the natural history of birds and their classification., A treatise or book on this science. |
| ornithopoda | noun pl. | An order of herbivorous dinosaurs with birdlike characteristics in the skeleton, esp. in the pelvis and hind legs, which in some genera had only three functional toes, and supported the body in walking as in Iguanodon. See Illust. in Appendix. |
| ornithotomy | noun | The anatomy or dissection of birds. |
| orthocenter | noun | That point in which the three perpendiculars let fall from the angles of a triangle upon the opposite sides, or the sides produced, mutually intersect. |
| orthodromic | adjective | Of or pertaining to orthodromy. |
| orthoepical | adjective | Of or pertaining to orthoepy, or correct pronunciation. |
| orthography | noun | The art or practice of writing words with the proper letters, according to standard usage; conventionally correct spelling; also, mode of spelling; as, his orthography is vicious., The part of grammar which treats of the letters, and of the art of spelling words correctly., A drawing in correct projection, especially an elevation or a vertical section. |
| orthometric | adjective | Having the axes at right angles to one another; — said of crystals or crystalline forms. |
| orthopedist | noun | One who prevents, cures, or remedies deformities, esp. in children. |
| orthopteran | noun | One of the Orthoptera. |
| orthoscopic | adjective | Giving an image in correct or normal proportions; giving a flat field of view; as, an orthoscopic eyepiece. |
| orthostichy | noun | A longitudinal rank, or row, of leaves along a stem. |
| orthotomous | adjective | Having two cleavages at right angles with one another. |
| orthotropal | adjective | Alt. of Orthotropous |
| orthotropic | adjective | Having the longer axis vertical; — said of erect stems. |
| orthoxylene | noun | That variety of xylene in which the two methyl groups are in the ortho position; a colorless, liquid, combustible hydrocarbon resembling benzene. |
| oryctognosy | noun | Mineralogy. |