| MOPV | monovalent oral poliovirus vaccine |
|---|---|
| OA | obstructive apnea; occipital artery; occipito-anterior; occiput anterior; octanoic acid; ocular albi... |
| OA/BVM | oral airway/bag-valve-mask |
| OAS | old age security; oral allergy syndrome; osmotically active substance |
| OAW | oral airways |
| water barometer | <physics> A barometer in which the changes of atmospheric pressure are indicated by the motion of a column of water instead of mercury. It requires a column of water about thirty-three feet in height. Source: Websters Dictionary (01 Mar 1998) |
|---|---|
| water bath | In chemistry, a vessel containing water, in which a container holding a substance to be heated or evaporated can be immersed. (05 Mar 2000) |
| water battery | 1. <physics> A voltaic battery in which the exciting fluid is water. 2. A battery nearly on a level with the water. Source: Websters Dictionary (01 Mar 1998) |
| water bear | <zoology> Any species of Tardigrada. Source: Websters Dictionary (01 Mar 1998) |
| water-bearer | <astronomy> The constellation Aquarius. Source: Websters Dictionary (01 Mar 1998) |
| water bed | A mattress in the form of a closed rubber bag filled with water; used to prevent or treat pressure sores by equalizing the distribution of the patient's weight against the support. (05 Mar 2000) |
| water beech | <botany> The American hornbeam. See Hornbeam. Source: Websters Dictionary (01 Mar 1998) |
| water beetle | <zoology> Any one of numerous species of aquatic beetles belonging to Dytiscus and allied genera of the family Dytiscidae, and to various genera of the family Hydrophilidae. These beetles swim with great agility, the fringed hind legs acting together like oars. Source: Websters Dictionary (01 Mar 1998) |
| water bird | <zoology> Any aquatic bird; a water fowl. Source: Websters Dictionary (01 Mar 1998) |
| water blackbird | <zoology> The European water ousel, or dipper. Source: Websters Dictionary (01 Mar 1998) |
| water boatman | <zoology> A boat bug. Source: Websters Dictionary (01 Mar 1998) |
| water brain | A disease of sheep; gid. Source: Websters Dictionary (01 Mar 1998) |
| water brash | <medicine> See Brash. Source: Websters Dictionary (01 Mar 1998) |
| water breather | <zoology> Any arthropod that breathes by means of gills. Source: Websters Dictionary (01 Mar 1998) |
| water buck | <zoology> A large, heavy antelope (Kobus ellipsiprymnus) native of Central Africa. It frequents the banks of rivers and is a good swimmer. It has a white ring around the rump. Called also photomok, water antelope, and waterbok. The name is also applied to other related species, as the leche (Kobus leche), which has similar habits. Source: Websters Dictionary (01 Mar 1998) |