whispering / evil suggestion
Feminine noun. Verb: وَسْوَسَ (quadriliteral, to whisper). الوَسْوَاس is also used as a noun meaning 'the whisperer' (Satan). From Surah an-Nās.
Surah an-Nās (114) seeks protection from Satan's whisperings in the hearts of people - one of the two protective surahs recited daily.