late 14c., "condition of being twisted or coiled; a fold or entanglement," originally in anatomy, from Late Latin involutionem (nominative involutio) "a rolling up," noun of action from past participle stem of Latin involvere "envelop, surround, roll into" (see involve). Related: Involutional.
invocation
invoice
invoke
involuntary
involute
involution
involve
involved
involvement
invulnerability
invulnerable