One ruminates about India always being poetic (8)
I believe the answer is:
reindeer
'one' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'ruminates about india always being poetic' is the wordplay.
I cannot really understand how this works, but
'about' could be 're' ('re' means regarding or about) and 're' is present in the answer.
'india' could be 'ind' (abbreviation) and 'ind' is found within the answer.
'always' could be 'eer' (poetic way of saying ever) and 'eer' is present in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for reindeer that I've seen before include "Dancer, perhaps" , "Santa's Prancer, say" , "Sleigh-puller" , "Animal that pulls Santa's sleigh" , "Eg, caribou" .)