Archaic term meaning quick-healing or having the quality of healing rapidly.
From Old English 'cūthe' (known, familiar) combined with 'heal' (to make whole), or possibly from 'kūth' (quick) + 'heal'—an obsolete construction.
This ultra-rare word vanished from English because we developed better medical understanding and more specific vocabulary, but it shows how people once personified healing as a property.
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