| COTTONWOODS | • cottonwoods n. Plural of cottonwood. • COTTONWOOD n. an American tree of the poplar genus, having seeds covered with abundant cotton-like hairs. |
| ODONTOLOGIST | • odontologist n. One who studies teeth. • ODONTOLOGIST n. a student of odontology. |
| ODONTOMATOUS | • odontomatous adj. Relating to an odontoma. • ODONTOMATOUS adj. like an odontoma, a tumour arising in connection with the teeth. |
| OPISTHOTONOS | • opisthotonos n. (Medicine) Sustained tetanic spasm in which the body is bent backwards and stiffened, as produced by various diseases. • OPISTHOTONOS n. extreme arching backwards of the spine and neck as a result of spasm of the muscles in that region, etc. |
| ODONATOLOGIST | • odonatologist n. One who studies odonatology. • ODONATOLOGIST n. one who studies dragonflies. |
| ODONTOLOGISTS | • odontologists n. Plural of odontologist. • ODONTOLOGIST n. a student of odontology. |
| ONOMATOLOGIST | • onomatologist n. One versed in the history of names. • ONOMATOLOGIST n. one who studies onomatology, the science of names. |
| ODONATOLOGISTS | • odonatologists n. Plural of odonatologist. • ODONATOLOGIST n. one who studies dragonflies. |
| ONOMATOLOGISTS | • onomatologists n. Plural of onomatologist. • ONOMATOLOGIST n. one who studies onomatology, the science of names. |
| OPISTHOTONOSES | • OPISTHOTONOS n. extreme arching backwards of the spine and neck as a result of spasm of the muscles in that region, etc. |
| POLYPROTODONTS | • polyprotodonts n. Plural of polyprotodont. • POLYPROTODONT n. any member of the Polyprotodontia, the suborder of marsupials, including opossums, dasyures, etc., with many small incisors. |
| HOMOEOTELEUTONS | • homoeoteleutons n. Plural of homoeoteleuton. • HOMOEOTELEUTON n. the use of words with similar endings in close proximity, also HOMEOTELEUTON. |
| ODONTOSTOMATOUS | • ODONTOSTOMATOUS adj. having biting or toothed jaws. |
| PHOTOCONDUCTORS | • photoconductors n. Plural of photoconductor. • PHOTOCONDUCTOR n. a photoconductive substance. |
| PHOTOIONISATION | • photoionisation n. (Physics) The ejection of electrons from an atom or other species following the absorption of photons. • PHOTOIONISATION n. ionization (as in the ionosphere) of a molecule or atom caused by absorption of radiant energy, also PHOTOIONIZATION. |
| PHOTOOXIDATIONS | • photooxidations n. Plural of photooxidation. • PHOTOOXIDATION n. oxidation under the influence of radiant energy, as light. |