| Words | Parts of Speech | Meaning/Definition/Similar Words |
|---|---|---|
| opacate | verb t. | To darken; to cloud. |
| opacity | noun | The state of being opaque; the quality of a body which renders it impervious to the rays of light; want of transparency; opaqueness., Obscurity; want of clearness. |
| opacous | adjective | Opaque. |
| opaline | adjective | Of, pertaining to, or like, opal in appearance; having changeable colors like those of the opal. |
| opalize | verb t. | To convert into opal, or a substance like opal. |
| opening | present participle & vb. noun | of Open, The act or process of opening; a beginning; commencement; first appearance; as, the opening of a speech., A place which is open; a breach; an aperture; a gap; cleft, or hole., Hence: A vacant place; an opportunity; as, an opening for business., A thinly wooded space, without undergrowth, in the midst of a forest; as, oak openings. |
| operand | noun | The symbol, quantity, or thing upon which a mathematical operation is performed; — called also faciend. |
| operant | adjective | Operative., An operative person or thing. |
| operate | verb i. | To perform a work or labor; to exert power or strengh, physical or mechanical; to act., To produce an appropriate physical effect; to issue in the result designed by nature; especially (Med.), to take appropriate effect on the human system., To act or produce effect on the mind; to exert moral power or influence., To perform some manual act upon a human body in a methodical manner, and usually with instruments, with a view to restore soundness or health, as in amputation, lithotomy, etc., To deal in stocks or any commodity with a view to speculative profits., To produce, as an effect; to cause., To put into, or to continue in, operation or activity; to work; as, to operate a machine. |
| opercle | noun | Any one of the bony plates which support the gill covers of fishes; an opercular bone., An operculum. |
| operose | adjective | Wrought with labor; requiring labor; hence, tedious; wearisome. |
| operous | adjective | Operose. |
| opetide | noun | Open time; — applied to different things, The early spring, or the time when flowers begin opening., The time between Epiphany and Ash Wednesday wherein marriages were formerly solemnized publicly in churches. [Eng.], The time after harvest when the common fields are open to all kinds of stock. |
| ophelic | adjective | Of, pertaining to, or designating, a substance (called ophelic acid) extracted from a plant (Ophelia) of the Gentian family as a bitter yellowish sirup, used in India as a febrifuge and tonic. |
| ophidia | noun pl. | The order of reptiles which includes the serpents., of Ophidion |
| ophiura | noun | A genus of ophiurioid starfishes. |
| ophryon | noun | The supraorbital point. |
| opianic | adjective | Of, pertaining to, or designating, an organic acid obtained by the oxidation of narcotine. |
| opianyl | noun | Same as Meconin. |
| opiated | adjective | Mixed with opiates., Under the influence of opiates. |
| opifice | noun | Workmanship. |
| opining | present participle & vb. noun | of Opine, Opinion. |
| opinion | noun | That which is opined; a notion or conviction founded on probable evidence; belief stronger than impression, less strong than positive knowledge; settled judgment in regard to any point of knowledge or action., The judgment or sentiment which the mind forms of persons or things; estimation., Favorable estimation; hence, consideration; reputation; fame; public sentiment or esteem., Obstinacy in holding to one’s belief or impression; opiniativeness; conceitedness., The formal decision, or expression of views, of a judge, an umpire, a counselor, or other party officially called upon to consider and decide upon a matter or point submitted., To opine. |
| opossum | noun | Any American marsupial of the genera Didelphys and Chironectes. The common species of the United States is Didelphys Virginiana. |
| oppidan | adjective | Of or pertaining to a town., An inhabitant of a town., A student of Eton College, England, who is not a King’s scholar, and who boards in a private family. |
| opplete | adjective | Alt. of Oppleted |
| opposal | noun | Opposition. |
| opposed | imp. & past participle | of Oppose |
| opposer | noun | One who opposes; an opponent; an antagonist; an adversary. |
| oppress | verb t. | To impose excessive burdens upon; to overload; hence, to treat with unjust rigor or with cruelty., To ravish; to violate., To put down; to crush out; to suppress., To produce a sensation of weight in (some part of the body); as, my lungs are oppressed by the damp air; excess of food oppresses the stomach. |
| optable | adjective | That may be chosen; desirable. |
| optical | adjective | Of or pertaining to vision or sight., Of or pertaining to the eye; ocular; as, the optic nerves (the first pair of cranial nerves) which are distributed to the retina. See Illust. of Brain, and Eye., Relating to the science of optics; as, optical works. |
| opulent | adjective | Having a large estate or property; wealthy; rich; affluent; as, an opulent city; an opulent citizen. |
| opuntia | noun | A genus of cactaceous plants; the prickly pear, or Indian fig. |
| opuscle | noun | Alt. of Opuscule |