Escaped ducks adopted by London college (5)
I believe the answer is:
loose
'escaped' is the definition.
(thesaurus)
'ducks adopted by london college' is the wordplay.
'ducks' becomes 'oo' (I've seen this in other clues).
'adopted by' is an insertion indicator (I've seen this in other clues).
'london college' becomes 'lse' (I've seen this in other clues).
'oo' put within 'lse' is 'LOOSE'.
(Other definitions for loose that I've seen before include "Baggy" , "Promiscuous" , "Untie; dissolute" , "Unfettered" , "Hanging" .)