People may lose money in them when dipping into loose coins (7)
I believe the answer is:
casinos
'people may lose money in them' is the definition.
I can't judge whether this defines the answer.
'when dipping into loose coins' is the wordplay.
'when' becomes 'as' (eg 'when I walked' means 'as I walked').
'dipping into' means one lot of letters goes inside another.
'loose' indicates an anagram (letters are loosened from their original positions).
'coins' is an anagram of 'cinos'.
'as' placed within 'cinos' is 'CASINOS'.
Can you help me to learn more?
(Other definitions for casinos that I've seen before include "Gambling establishments" , "Gaming rooms" , "Gambling places" .)