n. & v.
n. 1 a large tank or other vessel, esp. for holding liquids or something in liquid in the process of brewing, tanning, dyeing, etc. 2 a dyeing liquor in which a textile is soaked to take up a colourless soluble dye afterwards coloured by oxidation in air.
v.tr. (vatted, vatting) place or treat in a vat. vatful n. (pl. -fuls).
[ ME, southern & western var. of fat, OE ft f. Gmc ]