An editorial misreading in B. Lodge's 1873 edition of the Bodley MS of Palladius De re rustica for caumber (see quot. ?1440 at camberadj. for the correct reading), tentatively accepted in N.E.D. (1888) as perhaps showing a borrowing of ‘French canif or its Old French diminutive canivet’.
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1873 B. LodgePalladius on Husbondrie 42 Showe forth also the cannibe [L. curvos] knyves lite, In plantes yonge a branch awaie to take.
This entry has been updated (OED Third Edition, September 2018).