noun
whey
WAY/weɪ/
The watery liquid remaining after milk forms curds.
The cheesemaker drains the whey from the curds through a cloth.

Etymology
Old English hwæg already named whey, the watery part of milk left after curds form. Its deeper origin is unknown, so no earlier descriptive image can securely explain the name.
In context
the solids which are the curds which is what you make cheese out of and the liquids called whey
More examples
- A pale pool of whey collects beneath the strainer.
- She saves the whey to use instead of water in bread dough.
- Straining yogurt removes some whey and makes the yogurt thicker.
Forms
whey