3
infrequent
3
nocturnal
3
rare
3
decennial
3
odd
2
nightly(adjective, unusual, irregular, circadian)
2
sporadic
2
continually
2
spasmodic
1
occasional
1
aperiodic
1
formal
1
irregular
1
alternately
1
alternatingly
1
anniversary
1
at night
1
casual
1
chronically
1
continuingly
10 years ago|1k views|share |citing 
APASmart Define. (2015). daily thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/daily/thesaurus/antonyms
ChicagoSmart Define. 2015. "daily thesaurus" https://smartdefine.org/daily/thesaurus/antonyms (accessed September 24, 2026).
HarvardSmart Define 2015, daily thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/daily/thesaurus/antonyms>.
MLASmart Define. "daily thesaurus" 29 October 2015. Web. 24 September 2026. <https://smartdefine.org/daily/thesaurus/antonyms>