| ANTIPERIODIC | • antiperiodic adj. (Medicine) preventing the regular recurrence of symptoms. • antiperiodic adj. (Mathematics) Exhibiting antiperiodicity. • antiperiodic n. (Medicine) A drug that prevents the regular recurrence of symptoms. |
| APERIODICITY | • aperiodicity n. The condition of being aperiodic. • APERIODICITY n. the state of being aperiodic. |
| METAPERIODIC | • METAPERIODIC adj. as in metaperiodic acid. |
| PARAPERIODIC | • PARAPERIODIC adj. as in paraperiodic acid. |
| PERIODICALLY | • periodically adv. In a manner that is regular or periodic. • periodically adv. Intermittently or recurrently. • PERIODICAL adv. periodic. |
| PERIODONTIAS | • PERIODONTIA n. the branch of dentistry concerned with periodontal diseases. |
| PERIODONTICS | • periodontics n. (Dentistry) The study of supporting structures of teeth—gums, alveolar bone, cementum, and the periodontal… • PERIODONTICS n. the study of gums, as a branch of dentistry. |
| PERIODONTIST | • periodontist n. A dentist whose speciality is periodontics. • PERIODONTIST n. a dentist specialising in periodontics. |
| PERIONYCHIUM | • PERIONYCHIUM n. tissue surrounding a nail. |
| PERIOSTRACUM | • periostracum n. (Malacology) The proteinaceous outer sheath of many molluscan shells. • PERIOSTRACUM n. the horny outer layer of a mollusc's shell. |
| PHOTOPERIODS | • photoperiods n. Plural of photoperiod. • PHOTOPERIOD n. the period during every 24 hours when an organism is exposed to daylight. |
| SUPERIORSHIP | • superiorship n. The monastic role or position of superior. • SUPERIORSHIP n. the office of superior. |