Synonyms for Resistant (same or very similar meaning)
WordNet sense 1 (able to tolerate environmental conditions or physiological stress):
tolerant
WordNet sense 2 (capable of being borne or endured):
tolerable
WordNet sense 3 (relating to or conferring immunity (to disease or infection)):
immune
WordNet sense 4 (not susceptible to):
insusceptible, unsusceptible
WordNet sense 5 (disposed to or engaged in defiance of established authority):
insubordinate, resistive
WordNet sense 6 (boldly resisting authority or an opposing force):
defiant, noncompliant
WordNet sense 7 (incapable of absorbing or mixing with):
repellent
WordNet sense 8 (not capable of absorbing or soaking up (liquids)):
nonabsorbent, nonabsorptive
From the ODE community, based on WordNet
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