Verjuice

n. [ OE. vergeous, F. verjus, that is, the juice of green fruits; verd, vert, green + jus juice. See Verdant, and Juice. ] 1. The sour juice of crab apples, of green or unripe grapes, apples, etc.; also, an acid liquor made from such juice. [ 1913 Webster ]

2. Tartness; sourness, as of disposition. [ 1913 Webster ]