Oz couple dropping in as expected (5)
I believe the answer is:
ounce
'oz' is the definition.
(oz is the abbreviation for ounce)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for ounce that I've seen before include "A light weight - feline" , "One sixteenth of a pound" , "Imperial unit of weight" , "Unit of weight; cat" , "Small quantity - weight" .)