The term 'cut to the quick' is an idiom that means to cause someone emotional or physical pain. It originates from the practice of testing the sharpness of a blade by cutting through the skin quickly. The crossword solutions for this term are 'TRIM' and 'HURT', both of which have four letters. TRIM can refer to cutting something down to size, while HURT can refer to causing emotional or physical pain. Together, these two words accurately describe the meaning of the phrase 'cut to the quick'.