The Collaborative International Dictionary of English v.0.48:
Untidy \Un*ti"dy\, a. 1. Unseasonable; untimely. [Obs.] "Untidy tales." --Piers Plowman. [1913 Webster] 2. Not tidy or neat; slovenly. [1913 Webster] -- Un*ti"di*ly, adv. -- Un*ti"di*ness, n. [1913 Webster]WordNet (r) 3.0 (2006):
untidiness n 1: the condition of being untidy [ant: tidiness] 2: the trait of being untidy and messy [syn: untidiness, messiness] [ant: neatness, tidiness]