Like Sour Grapes is an idiom that refers to a feeling of envy or disappointment. It is used to describe someone who is unable to accept their failure or misfortune and instead expresses resentment towards those who have succeeded. The crossword solutions for this term are TART (4 letters) and ACIDIC (6 letters). TART means having a sharp, ACIDIC taste, while ACIDIC means having the properties of an acid. Both words accurately describe the sourness of grapes, which is often associated with the phrase Like Sour Grapes.