Definition of by blood
- My aunt and I are related by blood.
: the fluid that circulates in the heart, arteries, capillaries, and veins of a vertebrate animal carrying nourishment and oxygen to and bringing away waste products from all parts of the body
: a comparable fluid of an invertebrate
: a fluid resembling blood
: to stain or wet with blood
: to expose (a hunting dog) to sight, scent, or taste of the blood of its prey
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