Syntactic derivatives

кровяной blood (as modifier)
кровяное давление blood pressure
кровяное пятно a blood stain
кровавый bloody; blood-colored
кровавое пятно a blood stain
кровавая пена bloody froth (e.g. at the mouth of an overworked horse)
NB The adjective кровавый, above, has two meanings directly connected with the word кровь in the meaning of the entry: 1) "consisting of blood," e.g. кровавое пятно "a blood stain," кровавая лужа "a pool of blood," кровавая пена "bloody froth"; and 2) "covered with blood," e.g. кровавый бинт "a bloody bandage," кровавый нож "a bloody knife." But the adjective кровавый in the second meaning is not used to modify words describing clothing or parts of the body: the word окровавленный is used instead, e.g. окровавленная рубашка "a bloody/bloodied shirt," окровавленный висок "a bloody temple," окровавленный лоб "a bloody forehead," etc.