When things curdle, they turn from liquid gradually to solid, forming clumps along the way. If you leave milk out of the refrigerator long enough, it will curdle.

When a liquid curdles, it forms curds, or lumpy solid masses. In some cases this is deliberate, as when you make cheese or tofu. Other times, you might accidentally let something curdle, like a custard or sauce, or a forgotten container of cream at the back of your refrigerator. Curdle was originally crudle, from crud (later curd), "any coagulated substance," or "congeal."

Definitions of curdle
  1. verb
    go bad or sour
    “The milk curdled
    see moresee less
    type of:
    go bad, spoil
    become unfit for consumption or use
  2. verb
    turn from a liquid to a solid mass
    “his blood curdled
    see moresee less
    type of:
    clot, coagulate
    change from a liquid to a thickened or solid state
  3. verb
    turn into curds
    curdled milk”
    synonyms: clabber, clot
    see moresee less
    homogenise, homogenize
    become homogeneous or similar, as by mixing
    homogenise, homogenize
    break up the fat globules of
    homogenise, homogenize
    cause to become equal or homogeneous as by mixing
    show more antonyms...
    type of:
    change state, turn
    undergo a transformation or a change of position or action
Word Family

Test prep from the experts

Boost your test score with programs developed by’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.


  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week


  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week


  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week