red·ness
noun/ˈrednəs/
/ˈrednəs/
[uncountable, singular]- the fact of being red in colour, especially in a part of the body that is painful or swollen (= larger or rounder than normal)
颜色呈红色的事实，尤其是在身体疼痛或肿胀的部位（=比正常情况更大或更圆） - You may notice redness and swelling after the injection.
注射后可能会出现红肿。
- You may notice redness and swelling after the injection.