from
The Collaborative International Dictionary of English v.0.48
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.]
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When ruddy Ph?bus 'gins to welk in west. --Spenser.
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The church, that before by insensible degrees welked
and impaired, now with large steps went down hill
decaying. --Milton.
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