IPA: /ˈkæp.fəl/
KK: /ˈkæpˌfʊl/
The quantity of liquid that can be contained in a cap, often used as a measurement for liquids.
I added a capful of vinegar to the salad dressing.
Capful → It is formed from "cap" (from Old French *cape*, meaning a covering or lid) and "-ful" (meaning full of). The word "capful" means full of a cap or the amount that a cap can hold.
Think of a 'cap' as a covering that holds something, and '-ful' means full of — so a capful is the amount that a cap can hold.