sleazy

Etym. online:
1640s, "downy, fuzzy," later "flimsy, unsubstantial" (1660s), of unknown origin; one theory is that it is a corruption of Silesia, the German region, where thin linen or cotton fabric was made for export. Silesia in reference to cloth is attested in English from 1670s; and sleazy as an abbreviated form is attested from 1670), but OED is against this. Sense of "sordid" is from 1941. Related: Sleazily; sleaziness.