extramarital has definitions from the field of sexuality
1
[ adjective ] (sexuality) characterized by adultery

Examples

"an adulterous relationship" "extramarital affairs" "the extracurricular activities of a philandering husband"

Used in print

(Philip Reaves, "Who Rules the Marriage Bed?"...)

One such wife , Dr._Linden says , became disgusted with her weak husband and flurried through a series of extramarital affairs in the hope of finding a stronger man .

Related terms

illicit

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