5
blurred(adjective, weak, pale, faded)
5
imponderable(adjective, hard, knowledge, faint)
5
incomprehensible
5
trivial(adjective, hard, faint, littleness)
5
undetectable(adjective, hard, faint, subtle, unremarkable)
5
unrelatable
4
dull(adjective, weak, soft, gentle, low)
4
ephemeral(adjective, hard, faint, subtle, unremarkable)
4
fine(adjective, hard, slight, thin, faint)
4
hazy(adjective, weak, pale, faded)
4
low(adjective, calm, dull, quiet, weak)
4
minuscule(adjective, soft, gentle, minute, tiny)
4
pale(adjective, dull, weak, soft, gentle)
4
shadowy(adjective, hard, weak, faint, pale)
4
tenuous(weak, slight, fine, thin, pale)
4
unhearable(adjective, quiet, soft, low)
3
atomic
3
blurry
3
corpuscular
3
covert(adjective, invisible)
11 years ago|14k views|share |citing 
APASmart Define. (2015). imperceptible thesaurus. Retrieved September 27, 2026, from https://smartdefine.org/imperceptible/thesaurus/synonyms
ChicagoSmart Define. 2015. "imperceptible thesaurus" https://smartdefine.org/imperceptible/thesaurus/synonyms (accessed September 27, 2026).
HarvardSmart Define 2015, imperceptible thesaurus, Smart Define, viewed 27 September, 2026, <https://smartdefine.org/imperceptible/thesaurus/synonyms>.
MLASmart Define. "imperceptible thesaurus" 13 April 2015. Web. 27 September 2026. <https://smartdefine.org/imperceptible/thesaurus/synonyms>