The Collaborative International Dictionary of English v.0.48:
Inapt \In*apt"\, a. [Pref. in- not + apt: cf. F. inapte. Cf. Inept.] Unapt; not apt; unsuitable; inept. -- In*apt"ly, adv. -- In*apt"ness, n. [1913 Webster]WordNet (r) 3.0 (2006):
inaptness n 1: inappropriateness; "greater inaptness of expression would be hard to imagine" [syn: inaptness, inappositeness] [ant: appositeness, aptness]