He drew back and gave her a smile that made her blood thicken.

Gwalchmai sat, watching the blood on his arm thicken and dry.

Indeed they have no love of the cold; their blood thickens and their movements slow.

Also, as the body loses fluid, the blood thickens, which can lead to a heart attack or a stroke.

Very literally, the blood does not "thicken" in cold weather.

Their blood thickens, which helps them not to pass out but increases the risk that they will have strokes.

The blood rushed to her cheeks, swelled and thickened them.

He felt the blood in his veins thicken and slow.

His face was dark, as though the blood thickened purple beneath the skin.

Carpenter's blood was thickening on the carpet, which couldn't absorb the amount leaking out of him.