Sleek (slēk), a. [Compar.Sleeker (–ẽr); superl.Sleekest.] [OE. slik; akin to Icel. slīkr, and OE. sliken to glide, slide, G. schleichen, OHG. slīhhan, D. slik, slijk, mud, slime, and E. slink. Cf. Slick, Slink.] 1. Having an even, smooth surface; smooth; hence, glossy; as, sleek hair. Chaucer.
So sleek her skin, so faultless was her make. Dryden.
2. Not rough or harsh.
Those rugged names to our like mouths grow sleek. Milton.