Diminutive siblings (4)
I believe the answer is:
bros
This could be a double definition.
'diminutive' is the first definition.
Both the answer and definition are singular nouns.
Maybe you can see an association between them that I can't see?
'siblings' is the second definition.
(I've seen this in other clues)
Can you help me to learn more?
(Other definitions for bros that I've seen before include "Moss before this makes a gentlemen's outfitter" , "The Moss brothers" .)