EXTRACURRICULAR
adulterous, extramarital, extracurricular
(adjective) characterized by adultery; “an adulterous relationship”; “extramarital affairs”; “the extracurricular activities of a philandering husband”
extracurricular
(adjective) outside the regular duties of your job or profession
extracurricular
(adjective) outside the regular academic curriculum; “sports and drama are popular extracurricular activities”
Source: WordNet® 3.1
Etymology
Adjective
extracurricular (not comparable)
Outside of the normal curriculum of an educational establishment
Similarly outside of the normal duties of a job or profession
(informal) extramarital
Noun
extracurricular (plural extracurriculars)
(education) An activity outside the normal academic curriculum.
(informal) An activity beyond official duties of a job or profession.
(informal) An extramarital affair.
Source: Wiktionary