| optical |
of or having to do with the sense of sight or the eye. [2 definitions] |
| optician |
a person who makes or sells eyeglasses and contact lenses. |
| optimism |
the belief that things will turn out well or that there is always hope for something good to happen. |
| optimistic |
likely to be hopeful that things will work out well. |
| option |
the right, power, or freedom to choose. [2 definitions] |
| optional |
left to someone's choice; not required. |
| optometrist |
a person who is trained to examine people's eyes and to fit them with eyeglasses or contact lenses. |
| -or1 |
See "-er1" |
| OR1 |
abbreviation of "Oregon." |
| OR2 |
abbreviation of "operating room." |
| or |
used to indicate alternatives. [5 definitions] |
| oral |
spoken, rather than written; carried out by speaking. [2 definitions] |
| orange |
a round fruit with a reddish yellow peel. It is sweet and juicy on the inside. [4 definitions] |
| orangeade |
a soft drink made with orange juice or orange flavoring. |
| orangutan |
a large ape that lives in the rain forests of a few south Asian islands. Orangutans have long, red-brown fur and long arms. They spend most of their time in trees. They are a kind of primate. Orangutans are endangered. |
| orbit |
the curved path in which a planet, satellite, or spacecraft moves in a circle around another body. [3 definitions] |
| orchard |
a piece of land planted with fruit or nut trees. |
| orchestra |
a group of musicians who play different kinds of instruments and perform together. [3 definitions] |
| orchid |
a plant that bears showy flowers. Most orchids are found in the tropics. [3 definitions] |
| ordain |
to admit to the clergy as a priest, minister, or rabbi in a formal ceremony. [2 definitions] |
| ordeal |
a painful, difficult experience, or test of one's character. |