| 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] |
| occur |
to take place; happen. [3 definitions] |
| occurrence |
the process or fact of occurring. [2 definitions] |
| ocean |
the vast expanse of salt water covering approximately three quarters of the earth's surface. [3 definitions] |
| Oceania |
the region of the earth wherein are located the central, western, and southern Pacific islands, including Melanesia, Micronesia, and Polynesia. The region is sometimes considered to additionally include Australia, New Zealand, and the islands of the Malay Archipelago. |
| oceanography |
the branch of science that deals with the geography and other features of oceans. |
| ocelot |
a spotted wild cat of Central and South America, similar to but smaller than a leopard. |
| o'clock |
of or according to the clock. [2 definitions] |
| Oct. |
abbreviation of "October," the tenth month of the Gregorian calendar year, having thirty-one days. |
| oct- |
a variant of octo-. |
| octagon |
a two-dimensional figure with eight sides and eight angles; octangle. |
| octave |
a musical tone eight full tones above or below another tone, with twice or half as many vibrations per second as the other tone. [5 definitions] |
| octo- |
eight. |