[fen, in L. version of Avicenna, ad. Arab. fann species, class.] A section in Avicenna’s Canon.

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c. 1386.  Chaucer, Pard. T., 562.

        But certes I suppose that Avycen
Wrot never in canoun, ne in non fen,
Mo wonder sorwes of empoisonyng.

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1541.  R. Copland, Guydon’s Quest. Chirurg., Q iij. Sayth Auycen in his fyrste fen of the fyrste boke of his Canon.

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