Synonyms for Inactive (same or very similar meaning)
WordNet sense 1 (not reacting chemically):
unreactive
WordNet sense 2 (not involved in military operations):
nonoperational
WordNet sense 3 (not in physical motion):
motionless, static, still
WordNet sense 4 (not in motion):
nonmoving, unmoving
WordNet sense 5 (not active or activated):
quiescent
WordNet sense 6 (lacking in energy or will):
passive
WordNet sense 7 (not presently active):
latent
WordNet sense 8 ((of tumors e.g) slow to heal or develop and usually painless):
indolent
WordNet sense 9 (not in active use):
idle, unused
WordNet sense 10 ((of business) not active or brisk):
dull, slow, sluggish
WordNet sense 11 (requiring sitting or little activity):
sedentary
WordNet sense 12 (slow and apathetic):
inert, torpid
WordNet sense 13 (inactive but capable of becoming active):
dormant
From the ODE community, based on WordNet
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