3
endangered(adjective, weak, soft, unreliable)
3
exposed
3
forfeit(verb, disregard, fail, loosen, unfix)
3
free(verb, disregard, fail, loosen, unfix)
3
give up(verb, expression, phrasal verb, hold, disregard)
3
loose(verb, adjective, weak, disregard, fail)
3
loosen(verb, disregard, fail, unfix)
3
open(verb, adjective, disregard, fail, loosen)
3
questionable
3
release(noun, verb, disregard, fail, loosen)
3
risky(adjective, strong, safe)
3
undecided(adjective, clear, weak, soft, unreliable)
3
undefended(adjective, unprotected)
3
unreliable(adjective, weak, soft)
3
unstable(adjective, clear, weak, sound, soft)
3
unsustainable
3
untrustworthy(adjective, weak, soft, unreliable)
2
baneful
2
break(verb, destroy, agree, continue, face)
2
defenseless
11 years ago|5.4k views|share |citing 
APASmart Define. (2015). secure thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/secure/thesaurus/antonyms
ChicagoSmart Define. 2015. "secure thesaurus" https://smartdefine.org/secure/thesaurus/antonyms (accessed September 22, 2026).
HarvardSmart Define 2015, secure thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/secure/thesaurus/antonyms>.
MLASmart Define. "secure thesaurus" 10 April 2015. Web. 22 September 2026. <https://smartdefine.org/secure/thesaurus/antonyms>