tass /tæs/ noun4 •(dialect, Scotland) A cup or cupful."Here, Dougal," said the Laird, "gie Steenie a tass of brandy down stairs, till I count the siller and write the receipt." — 1824 •An Oriental silk fabric, with gold or silver thread. •Synonym of tasse. •(no longer used, rare) A heap, pile. formstasses