Meaning

noun a blemish made by dirt

noun an act that brings discredit to the person who does it

verb dry (ink) with blotting paper

originFrom Middle English blot (“blot, spot, stain, blemish”). Perhaps from Old Norse *blettr (“blot, stain”) (only attested in documents from after Old Norse transitioned to Icelandic blettur), or from Old French bloche (“clod of earth”).

Etymology from Wiktionary, CC BY-SA 3.0