| ocher |
any of several iron oxides mixed with clay or sand, ranging in color from pale yellow to reddish brown, and used as pigments. [2 definitions] |
| ochlocracy |
government by a lawless crowd of people; mobocracy. |
| -ock |
small. |
| o'clock |
of or according to the clock. [2 definitions] |
| ocotillo |
a spiny shrub that resembles a cactus, found in the dry regions of Mexico and the southwestern United States. |
| OCS1 |
abbreviation of "Officer Candidate School." |
| OCS2 |
abbreviation of "Old Church Slavonic." |
| Oct. |
abbreviation of "October," the tenth month of the Gregorian calendar year, having thirty-one days. |
| oct- |
a variant of octo-. |
| octa- |
a variant of octo-. |
| octagon |
a two-dimensional figure with eight sides and eight angles; octangle. |
| octahedron |
a three-dimensional figure with eight flat surfaces. |
| octane |
any of a group of oily, colorless isomeric hydrocarbons, some of which are obtained during the distillation of petroleum. [2 definitions] |
| octane number |
a number that designates the antiknock properties of a gasoline, based on the percentage of isooctane in it; octane rating. |
| octane rating |
see "octane number." |
| octant |
an eighth of a circle, or the arc or area it includes. [4 definitions] |
| 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] |
| octavo |
a page or book size resulting from folding a printer's sheet of paper into eight leaves, each about six inches by nine inches. |
| octet |
a group of eight singers or musicians. [3 definitions] |
| octillion |
the number represented by the Arabic numeral 1027. [2 definitions] |
| octo- |
eight. |