Extended Strong's Hebrew Lexicon (Brown-Driver-Briggs based)
be unfaithful
Usage: 1) to act unfaithfully, act treacherously, transgress, commit a trespass 1a) (Qal) to act unfaithfully or treacherously 1a1) against man 1a2) against God 1a3) against devoted thing 1a4) against husband