late 14c., from Old French infinité "infinity; very large number or quantity" (13c.), from Latin infinitatem (nominative infinitas) "boundlessness, endlessness," from infinitus boundless, unlimited" (see infinite). Latin infinitas was used as a loan-translation of Greek apeiria "infinity," from apeiros "endless."
infinite
infinitely
infinitesimal
infinitive
infinitude
infinity
infirm
infirmary
infirmity
inflame
inflammable