| ANTHEROZOOID | • antherozooid n. Alternative form of antherozoid. • ANTHEROZOOID n. a motile male gamete produced in an antheridium, also ANTHEROZOID. |
| CHRONOLOGIST | • chronologist n. A person skilled in chronology. • CHRONOLOGIST n. an expert in chronology, also CHRONOLOGER. |
| MONOCHROMIST | • monochromist n. An artist working in the monochromatic style. • MONOCHROMIST n. a person who practises monochrome. |
| MONOSTROPHIC | • monostrophic adj. Of or pertaining to monostrophe. • monostrophic n. A monostrophe. • MONOSTROPHIC adj. having the same strophic or stanzaic structure throughout. |
| MONOTRICHOUS | • monotrichous adj. Having a single flagellum. • MONOTRICHOUS adj. of bacteria, having a single flagellum, also MONOTRICHIC. |
| MOTHPROOFING | • mothproofing v. Present participle of mothproof. • MOTHPROOF v. to proof against moths. |
| ORNITHOLOGIC | • ornithologic adj. Of or relating to ornithology; ornithological. • ORNITHOLOGIC adj. relating to ornithology, also ORNITHOLOGICAL. |
| ORNITHOMORPH | • ornithomorph n. A figure in ancient art resembling a bird. • ORNITHOMORPH n. a figure or design in the form of a bird. |
| ORNITHOSCOPY | • ornithoscopy n. Birdwatching. • ORNITHOSCOPY n. bird watching. |
| ORTHOCOUSINS | • orthocousins n. Plural of orthocousin. • ORTHOCOUSINS n. the children of two brothers or two sisters. |
| ORTHODONTIAS | • ORTHODONTIA n. the rectification of crookedness in the teeth, also ORTHODONTICS. |
| ORTHODONTICS | • orthodontics n. (Medicine) A specialty of dentistry concerned with correcting misalignment of teeth. • ORTHODONTICS n. the rectification of crookedness in the teeth, also ORTHODONTIA. |
| ORTHODONTIST | • orthodontist n. An orthodontic dentist. • ORTHODONTIST n. one who practises orthodontics. |
| ORTHOTONESIS | • orthotonesis n. The accentuation of a proclitic or enclitic. • ORTHOTONESIS n. accentuation of a proclitic or enclitic, as opposed to enclisis. |
| OVERSHOOTING | • overshooting v. Present participle of overshoot. • OVERSHOOT v. to shoot over or beyond one's target. |
| POORMOUTHING | • poormouthing v. Present participle of poormouth. • POORMOUTH v. to complain about being poor. |