In a manner relating to cognition or mental processes; from the perspective of thinking and understanding.
From cognitive (relating to knowing and thinking) plus the adverbial suffix -ly. Cognitive derives from Latin cognoscere (to know).
This adverb is actually quite common in modern psychology and neuroscience—when researchers say someone is 'cognitively impaired' or something is 'cognitively demanding,' they're precisely describing the thinking demands or abilities!
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