Confirm group of women beamed around son (7)
I believe the answer is:
witness
'confirm' is the definition.
(thesaurus)
'group of women beamed around son' is the wordplay.
'group of women' becomes 'WI' (Women's Institute).
'beamed' becomes 'sent' ('send' can be a synonym of 'beam').
'around' says the letters should be written backwards.
'son' becomes 's' (genealogical abbreviation for son).
'sent' reversed gives 'tnes'.
'wi'+'tnes'+'s'='WITNESS'
(Other definitions for witness that I've seen before include "See (an event or crime)" , "Attest" , "Spectator" , "Observer" , "Court testifier" .)