Pronunciation: (kûr'dl), [key]
—v.t., v.i., -dled, -dling.
1. to change into curd; coagulate; congeal.
2. to spoil; turn sour.
3. to go wrong; turn bad or fail: Their friendship began to curdle as soon as they became business rivals.
4. curdle the or one's blood, to fill a person with horror or fear; terrify: a scream that curdled the blood.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.