Dictionary

curdle

-verb

1. (ambitransitive) To form curds so that it no longer flows smoothly; to cause to form such curds. (usually said of milk)
2. (ambitransitive) To clot or coagulate; to cause to congeal, such as through cold. (metaphorically of blood)
3. (transitive) To cause a liquid to spoil and form clumps so that it no longer flows smoothly