There are numerous synonyms available for the phrase "turns red," each of which is used to describe the process by which something changes from its natural color to a shade of red. Blush, flush, redden, and glow are some of the most common synonyms for this phrase. Blush generally describes a temporary redness that may occur due to embarrassment, while flush often refers to a sudden and intense redness caused by exercise or excitement. Redden implies a gradual change in color, while glow is typically used to describe a brighter, more intense shade of red. All these words can convey a subtle difference in meaning when used to describe the process of turning red.