adjective
not true to allegiance or duty
a faithless husband
Synonyms: disloyal, false, perfidious, recreant, traitorous, treacherous, unfaithful, unloyal, untrue
Related Word: capricious, fickle, inconstant, unstable; fluctuating, wavering; changeable, changeful
Contrasted words: constant, loyal, resolute, staunch, steadfast, true
Antonyms: faithful