Being Irish, is popularly called Red (6)
I believe the answer is:
setter
'being' is the definition.
The definition and answer can be both animals as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for setter that I've seen before include "Jelly, perhaps" , "Late evening sun is a" , "Dog found in street" , "Puzzle creator" , "Crossword composer" .)