Source : Webster's Revised Unabridged Dictionary (1913)

Welked \Welked\, v. t.
   See {Whelked}.

Welk \Welk\, v. i. [imp. & p. p. {Welked}; p. pr. & vb. n.
   {Welking}.] [OE. welken; cf. D. & G. welken to wither, G.
   welk withered, OHG. welc moist. See {Welkin}, and cf.
   {Wilt}.]
   To wither; to fade; also, to decay; to decline; to wane.
   [Obs.]

         When ruddy Ph?bus 'gins to welk in west. --Spenser.

         The church, that before by insensible degrees welked
         and impaired, now with large steps went down hill
         decaying.                                --Milton.