Adulterous (adjective)

1. Having sexual intercourse with someone other than one's spouse, especially a married person.
2. Not pure; mixed with foreign or inferior ingredients.

Origin:

Late middle english: from old french adultere, from latin adulterium, from adulter "adulterer".

Examples:

1. He was accused of adulterous behavior.
2. She was labelled as an adulterous woman.
3. The adulterous relationship caused the end of their marriage.
4. The adulterous man was punished by the society.
5. It was found that the food was adulterous with harmful chemicals.