weak: P. and V. ἀσθενής, P. ἄρρωστος, ἀπειρηκώς, V. ἄναλκις, ἀμαυρός, ἄναρθρος.
infirm of purpose: Ar. and P. μαλακός, Ar. and V. μαλθακός; see cowardly.
be infirm, v.: P. and V. ἀσθενεῖν. P. ἀρρωστεῖν.