WordNet: foible, idiosyncrasy, mannerism

a behavioral attribute that is distinctive and peculiar to an individual

• hypernym distinctiveness, peculiarity, speciality, specialness, specialty

foible

• (suomi) heikko kohta (synonyymi)

idiosyncrasy

• (englanti) idiosyncratic (derivationally related)
• (suomi) ominaispiirre (synonyymi)

mannerism

• (suomi) maneeri (synonyymi)