- clot (n.)
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- Old English clott "a round mass, lump," akin to Dutch kloot "ball," Danish klods "a block, lump," German Klotz "lump, block;" probably related to cleat and clod.
- clot (v.)
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- early 15c., from clot (n.). Of fluids from 1590s. Related: Clotted; clotting.