Contemplated putting us in sea (5)
I believe the answer is:
mused
'contemplated' is the definition.
('muse' can be a synonym of 'contemplate')
'us in sea' is the wordplay.
'in' means one lot of letters goes inside another.
'sea' becomes 'med' (abbreviation of Mediterranean).
'us' placed within 'med' is 'MUSED'.
'putting' is the link.
(Other definitions for mused that I've seen before include "Was absorbed in thought" , "Closer" , "Thought (to oneself)" , "Reflected in silence" , "Was deep in thought" .)