make your blood run cold
make (one's) blood run cold
To cause one to feel frightened or unnerved. The screams coming from the old, dark house made my blood run cold. That gruesome scene in the new horror movie made our blood run cold.
make your blood run coldor
make your blood freeze
If something makes your blood run cold or makes your blood freeze, it frightens or shocks you very much. The rage in his eyes made her blood run cold. It makes my blood run cold to think what this poor, helpless child must have gone through. Note: You can also simply say that your blood runs cold or your blood freezes. Then his blood froze. For there in the crowd was the one face he didn't want to see. Note: You can use blood-freezing before a noun, to say that something is extremely frightening or shocking. It's a blood-freezing image of corrupted innocence. Note: In medieval times, some people believed that certain emotions changed the temperature of the blood.
make your blood run coldhorrify you.
The previous three phrases all come from the medieval physiological scheme of the four humours in the human body (melancholy, phlegm, blood, and choler). Under this scheme blood was the hot, moist element, so the effect of horror or fear in making the blood run cold or curdling (solidifying) it was to make it unable to fulfil its proper function of supplying the body with vital heat or energy. The blood boiling was a supposedly dangerous overreaction to strong emotion.