| a white, crystalline, water-soluble powder, C4H5KO6, used chiefly as an ingredient in baking powders and in galvanic tinning of metals. Also called potassium bitartrate, potassium acid tartrate. Compare tartar (def. 3). |
| cream of tartar n. See potassium bitartrate. |
| potassium bitartrate n. A white, acid, crystalline solid or powder, KHC4H4O6, used in baking powder, in the tinning of metals, and as a component of laxatives. Also called cream of tartar. |