D defs.my
Entry 1 sense Webster, 1913

Couth

/(k??th)/ · IPA /kuθ/
01 imp. & p. p. Could; was able; knew or known; understood.
  1. 1.
    Could; was able; knew or known; understood.[Obs.]
    “Above all other one Daniel He loveth, for he couth well Divine, that none other couth; To him were all things couth, As he had it of God's grace.” — Gower.