Definition of phthiriasis in English:

phthiriasis

noun

Medicine
  • Infestation with lice; (in later use) specifically infestation with pubic (crab) lice (Phthirus pubis).

Origin

Mid 16th century; earliest use found in Thomas Elyot (c1490–1546), humanist and diplomat. From classical Latin phthīriāsis infestation with lice from ancient Greek ϕθειρίασις from ϕθειριᾶν to be infested with lice (from ϕθείρ louse: see note) + -σις.

Pronunciation

phthiriasis

/(f)θʌɪˈrʌɪəsɪs//(f)θɪˈrʌɪəsɪs/