Bleed, in this context, refers to the spreading or transfer of color from one fabric or material to another, usually due to improper washing or dyeing. It can happen when a colored item, such as a red sock, accidentally gets mixed with a load of white clothes and the color from the red sock spreads onto the white clothes, causing them to become stained or discolored.
Note: The provided meaning of the answer is for the latest New York Times crossword puzzle clue: What an errant red sock may do in a load of whites. Explanations are generated by AI and may be inaccurate.