The Collaborative International Dictionary of English v.0.48:

Sleek \Sleek\, v. t. [imp. & p. p. Sleeked;p. pr. & vb. n.
   Sleeking.]
   To make even and smooth; to render smooth, soft, and glossy;
   to smooth over.
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         Sleeking her soft alluring locks.        --Milton.
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         Gentle, my lord, sleek o'er your rugged looks. --Shak.
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