The term 'grapes' can be broken down into four crossword solutions: SOUR (4 letters), UVA (3 letters), UVAE (4 letters), and UVAS (4 letters). SOUR refers to the acidic taste of grapes, which is due to their high concentration of malic acid. UVA, UVAE, and UVAS are all varieties of grapes, with UVA being the most common variety. UVAE is a hybrid of UVA and Muscat of Alexandria, while UVAS is a hybrid of UVA and Muscat Hamburg.