Meaning

noun material used to daub walls

noun a blemish made by dirt

noun an unskillful painting

originFrom Middle English daub (noun), from Middle English dauben (“to plaster or whitewash; cover with clay; bespatter”, verb), from Old Northern French dauber (“to whitewash; plaster”), of uncertain origin. Probably from Latin dealbāre (“to whiten thoroughly”), which would make it a doublet of dealbate.

Etymology from Wiktionary, CC BY-SA 3.0