Synonyms of the word

two-timing

• v. present participle of two-time.
• adj. Who has two-timed another person.
• n. The practice of being sexually unfaithful.

adulterous

• adj. Of, or characterized by adultery.

cheating

• v. present participle of cheat.
• n. An act of deception, fraud, trickery, imposture, or imposition.
• n. (cinematography) The arrangement of people or items in a film so as to give the (false) impression that…
• adj. Unsporting or underhand.
• adj. Unfaithful or adulterous.

unfaithful

• adj. Not having religious faith.
• adj. Not keeping good faith; disloyal; not faithful.
• adj. Not honest or upright.
• adj. (translation studies) which doesn't faithfully render the meaning of the source language; incorrect.
• adj. Adulterous.