Answer: verjuice

AnswerCrossword Clue
verjuiceof or pertaining to verjuice
verjuiceto make sour with the juice of crabapples
verjuicesourness, as of temper or expression
verjuiceacid liquor made from the sour juice of crab apples, unripe grapes, etc., formerly much used for culinary and other purposes
verjuicesour in temper, expression, etc.