A gross baby, born today in a field? (8)
I believe the answer is:
agrarian
'born today in a field?' is the definition.
The answer and definition are different parts of speech. However, past participle verbs and adjectives can occasionally mean the same thing.
'a gross baby' is the wordplay.
'gross' becomes 'gr' (abbreviation).
'baby' becomes 'arian' (I can't justify this - if you can you should believe this answer much more).
'a'+'gr'+'arian'='AGRARIAN'
Can you help me to learn more?
(Other definitions for agrarian that I've seen before include "in the country" , "Relating to farmland" , "Relating to agriculture" , "Land reformer" , "politically reformist" .)