| obliterate |
to erase or make unrecognizable by erasing. [2 definitions] |
| oblivion |
the state or condition of being entirely forgotten. [2 definitions] |
| oblivious |
not conscious or paying attention; unknowing or unaware (usu. fol. by "to" or "of"). [2 definitions] |
| oblong |
having one dimension longer than the other, as in a rectangle or ellipse; elongated. [2 definitions] |
| obloquy |
abuse or censure, esp. as directed at one by many or by the general public; calumny. [2 definitions] |
| obnoxious |
extremely unpleasant or irritating. |
| oboe |
a slender double-reed woodwind instrument, consisting of a long, usu. wooden tube with finger holes or keys along it, which makes a penetrating, melancholy sound. |
| obs. |
abbreviation of "obsolete," no longer in use, as a word or expression, or a type of implement or equipment. [2 definitions] |
| obscene |
offensive to accepted views of morality and decency, or to one's own sense of morality and decency. [3 definitions] |
| obscenity |
the state, condition, or crime of being obscene; indecency, lewdness, or repulsiveness. [2 definitions] |
| obscurantism |
active opposition to intellectual enlightenment, esp. by withholding knowledge from the public. [2 definitions] |
| obscure |
weakly or poorly illuminated. [6 definitions] |
| obscurity |
the state or condition of being dark or dim. [3 definitions] |
| obsequious |
showing or tending to show servile obedience or deference; fawning. |
| obsequy |
(usu. pl.) a funeral rite or ceremony. |
| observable |
able to be observed; visible. [2 definitions] |
| observance |
compliance or obedience. [4 definitions] |
| observant |
watching carefully; alert; attentive. [2 definitions] |
| observation |
the act or an instance of observing. [5 definitions] |
| observation car |
a railway car with large windows from which passengers may observe the scenery. |
| observation post |
a forward military position from which the enemy can be observed and artillery fire can be directed. |