Father's lemonade (3)
I believe the answer is:
pop
This clue might be a double definition.
'father's' is the first definition.
(pop is a kind of father)
'lemonade' is the second definition.
The answer and definition can be both things that one consumes for nourishment as well as being singular nouns.
Maybe they are linked in a way I don't understand?
Can you help me to learn more?
(Other definitions for pop that I've seen before include "US fizzy drink and type of music" , "Sound of a balloon bursting" , "'American Dad'!" , "Modern music for the masses" , "Palindrome of music for the young" .)