Able to be thought of, imagined, or worked out through thinking; possible to figure out or devise by thought.
From Latin 'excogitabilis,' derived from 'excogitare' (to think out thoroughly). The suffix '-able' means capable of being.
This word captures something important about human thought—that we can imagine or work out things that don't yet exist, which is the basis of invention and creativity, yet it's fallen out of modern use almost entirely.
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