To know, perceive, or become aware of something; to take notice of.
From Old French cognoistre, derived from Latin cognoscere (to know, to become acquainted with, to recognize). The verb entered Middle English and represents the British spelling of American 'cognize.'
This verb is pretty much extinct in everyday speech—you won't hear people say 'I cognised the problem' anymore—but it survives in formal legal and philosophical writing as part of the 'cognise/cognisance' family!
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