Huge tail of distinct, brightly coloured bird (7)
I believe the answer is:
ostrich
'bird' is the definition.
(ostrich is a kind of bird)
'huge tail of distinct brightly coloured' is the wordplay.
'huge' becomes 'os' (abbreviation for outsize).
'tail of' suggests the final letters.
'brightly coloured' becomes 'rich' (I can't justify this - if you can you should believe this answer much more).
The last letter of 'distinct' is 't'.
'os'+'t'+'rich'='OSTRICH'
Can you help me to learn more?
(Other definitions for ostrich that I've seen before include "non-flyer?" , "Runner" , "source of showy feathers" , "Creature" , "Largest non-flying bird" .)