To an extent how teams are formed (8)
I believe the answer is:
somewhat
'to an extent' is the definition.
(I've seen this in another clue)
'how teams are formed' is the wordplay.
'are formed' indicates anagramming the letters.
'how'+'teams'='howteams'
'howteams' with letters rearranged gives 'SOMEWHAT'.
(Other definitions for somewhat that I've seen before include "Quite" , "To some degree, sort of" , "up to a point" , "Rather, a little" , "To an extent, a little" .)