The Collaborative International Dictionary of English v.0.48:

Kythe \Kythe\, Kithe \Kithe\ (k[imac][th]), v. t. [imp. Kydde,
   Kidde (k[i^]d"de); p. p. Kythed, Kid; p. pr. & vb. n.
   Kything.] [OE. kythen, kithen, cu[eth]en, to make known,
   AS. c[=y][eth]an, fr. c[=u][eth] known. [root]45. See
   Uncouth, Can to be able, and cf. Kith.]
   To make known; to manifest; to show; to declare. [Obs. or
   Scot.]
   [1913 Webster]

         For gentle hearte kytheth gentilesse.    --Chaucer.
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