The sticking point in an argument? (3)
I believe the answer is:
gum
'the sticking point' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'in an argument?' is the wordplay.
'in' says the answer is hidden in the clue.
'GUM' is hidden within 'argument'.
Can you help me to learn more?
(Other definitions for gum that I've seen before include "Stuff to chew" , "Prepartion for sticking or chewing" , "Gingeva is its technical name" , "seal" , "Glue; jelly-like sweet" .)