Group of boys that is ejected from women’s loos (4)
I believe the answer is:
lads
'group of boys' is the definition.
(lad can mean a boy or young man)
'that is ejected from women's loos' is the wordplay.
'that is' becomes 'ie' (short for Latin 'id est', 'that is').
'ejected from' is a deletion indicator.
'women's loos' becomes 'ladies' (ladies' toilets).
'ladies' with 'ie' taken out is 'LADS'.
(Other definitions for lads that I've seen before include "Boys, young fellows" , "Fellows, chaps" , "Youngsters" , "Young men" , "Fellows, blokes" .)