11
by the way(verb, expression, idiom, adverb, phrasal verb)
10
incidentally(adverb, occasion, aside, irrelation)
6
by the by(verb, adverb, phrasal verb, occasion, irrelation)
5
in passing(expression, idiom, adverb, aside, casually)
4
apropos
3
en passant(expression, idiom, occasion, irrelation)
3
extraneously(adverb, extraneously)
3
extrinsically(adverb, extraneously)
2
offhand
2
passing
2
speaking of(adverb, aside, incidentally)
1
amid
1
amidst
1
among
1
amongst
1
as to(adverb, aside, incidentally)
1
betwixt
1
by the bye(adverb, aside, casually, incidentally, accidentally)
1
casually
1
disjointedly(adverb, extraneously)
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APASmart Define. (2015). parenthetically thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/parenthetically/thesaurus/synonyms
ChicagoSmart Define. 2015. "parenthetically thesaurus" https://smartdefine.org/parenthetically/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, parenthetically thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/parenthetically/thesaurus/synonyms>.
MLASmart Define. "parenthetically thesaurus" 14 April 2015. Web. 20 September 2026. <https://smartdefine.org/parenthetically/thesaurus/synonyms>