| obscene |
offensive to accepted views of morality and decency, or to one's own sense of morality and decency. [3 definitions] |
| obscure |
weakly or poorly illuminated. [6 definitions] |
| observation |
the act or an instance of observing. [5 definitions] |
| observatory |
a building containing equipment for making astronomical or other kinds of scientific observations. |
| observe |
to perceive; see. [10 definitions] |
| observer |
someone who observes an event such as a meeting but does not participate in it. [2 definitions] |
| obsolete |
no longer in use, as a word or expression, or as a type of implement or equipment. [2 definitions] |
| obstacle |
that which impedes or prevents forward movement or progress; obstruction. |
| obstinate |
holding stubbornly to one's own ideas or purposes; unwilling to change. [2 definitions] |
| obstruct |
to clog or block. [3 definitions] |
| obstruction |
something that obstructs; obstacle or impediment. [3 definitions] |
| obtain |
to gain possession of; acquire. [2 definitions] |
| obtuse angle |
an angle greater than 90 degrees and less than 180 degrees. |
| obvious |
easily understood, recognized, or seen; apparent. [2 definitions] |
| obviously |
in a way that is easy to see or understand; clearly. [2 definitions] |
| occasion |
an incident or event, or the time at which it happens. [5 definitions] |
| occasional |
occurring infrequently or irregularly. [3 definitions] |
| occasionally |
at times; now and then; infrequently. |
| occupant |
one, or a group, that occupies a place or position. [2 definitions] |
| occupation |
a person's normal way of earning a livelihood; profession. [5 definitions] |
| occupy |
to control (territory or the like) after seizure. [4 definitions] |