phthiriasis

noun
phthi·​ri·​a·​sis | \ thə-ˈrī-ə-səs How to pronounce phthiriasis (audio) , thī- How to pronounce phthiriasis (audio) \
plural phthiriases\ -​ˌsēz How to pronounce phthiriases (audio) \

Medical Definition of phthiriasis

: pediculosis especially : infestation with pubic lice