| 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. |
| observatory |
a building containing equipment for making astronomical or other kinds of scientific observations. |
| observe |
to perceive; see. [9 definitions] |
| observer |
someone who observes an event such as a meeting but does not participate in it. [2 definitions] |
| obsess |
to preoccupy the mind or emotions of (someone) excessively or abnormally. |
| obsession |
that which preoccupies one's mind or emotions excessively or abnormally. [2 definitions] |