5
adulterous(adjective, fickle, untrustworthy, unprincipled, unfaithful)
4
extramarital(adjective, illicit)
4
additional
3
after-school
3
external
2
outside
1
extra-curricular
1
illicit(adjective, unfaithful, cheating)
1
tertiary
0
amateurish
0
collegiate
0
dirty
0
extramural
0
foresworn(fickle, untrustworthy, unprincipled, dirty-dealing)
0
foul
0
intramural
0
lubricious(fickle, untrustworthy, unprincipled, dirty-dealing)
0
optional
0
unassured(fickle, untrustworthy, unprincipled)
0
unfaithful(fickle, untrustworthy, unprincipled, cheating, dirty-dealing)
10 years ago|1.9k views|share |citing 
APASmart Define. (2015). extracurricular thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/extracurricular/thesaurus/synonyms
ChicagoSmart Define. 2015. "extracurricular thesaurus" https://smartdefine.org/extracurricular/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, extracurricular thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/extracurricular/thesaurus/synonyms>.
MLASmart Define. "extracurricular thesaurus" 3 November 2015. Web. 21 September 2026. <https://smartdefine.org/extracurricular/thesaurus/synonyms>