The colour blood red is a dark shade of the colour red meant to resemble the colour of human blood (which is composed of oxygenated red erythrocytes, white leukocytes, and yellow blood plasma). It is the iron in hemoglobin specifically that gives blood its red colour.

blood red noun [ U ] uk / ˌblʌd ˈred / us / ˌblʌd ˈred / Add to word list Add to word list a bright red colour like fresh blood

blood-red adjective us / ˌblʌd ˈred / uk / ˌblʌd ˈred / of a bright red color like fresh blood:

blood-red [ bluhd - red ] Phonetic (Standard)IPA adjective of the deep-red color of blood: a fiery, blood-red sunset.