Group finds bed next to lake (7)
I believe the answer is:
coterie
'group' is the definition.
(term for a group of associated people)
'bed next to lake' is the wordplay.
'bed' becomes 'cot' (cot is a type of bed).
'next to' means one lot of letters go next to another.
'lake' becomes 'erie' (Lake Erie is one of the Canadian/US 'Great Lakes').
'cot'+'erie'='COTERIE'
'finds' acts as a link.
(Other definitions for coterie that I've seen before include "Set" , "Select group" , "Exclusive group with shared interests" , "Small exclusive group of people" , "Group, band" .)