Phrasal Verb: Cheat on
Meaning: Be sexually unfaithful
Example: She CHEATED ON me with my friend.
Meaning: Deceive or betray, often in a sexual and/or emotional context
Example: She thought he had always been faithful to her, but he had been CHEATING ON her ever since their wedding day (with one of the bridesmaids).
Other Phrasal Verbs
We have 2 phrasal verbs with 'CHEAT'