i Register
In some senses, cruor is marked as obsolete. Watch for register when choosing this word.
noun
The colouring matter of the blood.
The clotted portion of coagulated blood, containing the colouring matter; gore.
The boy is pinched and bled, heated and cooled, sprinkled with powders, spread with salves and a gritty mucilage of peony seeds and cat’s cruor.