Team learn as being thrashed (7)
I believe the answer is:
arsenal
'team' is the definition.
(Arsenal football club)
'learn as being thrashed' is the wordplay.
'being thrashed' indicates an anagram (letters beaten or thrashed around).
'learn'+'as'='learnas'
'learnas' anagrammed gives 'ARSENAL'.
(Other definitions for arsenal that I've seen before include "Store of weapons or English soccer team." , "Premier League side founded by munitions workers in 1886" , "stock" , "Armoury - London football club" , "London premiership football team" .)