An avian inflammation (6)

I believe the answer is:

thrush

I'm a little stuck... Click here to teach me more about this clue!

'an avian inflammation' is the definition.
The answer and definition can be both states of affairs as well as being singular nouns.
Perhaps you can see an association between them that I can't see?

This is the entire clue.

Can you help me to learn more?

(Other definitions for thrush that I've seen before include "Bird - fungal disease" , "Speckle-breasted songbird" , "Songbird - fungal infection" , "Infection of the mouth and throat" , "Songbird with brownish back and speckled breast" .)

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.