— curdler , n.
/kerr"dl/ , v.t., v.i., curdled, curdling .
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.
[ 1580-90; CURD + -LE ]