Lower to the sea bed, strangely enough (6)
I believe the answer is:
debase
'lower' is the definition.
(thesaurus)
'the sea bed strangely enough' is the wordplay.
'strangely enough' indicates an anagram.
'sea'+'bed'='seabed'
'seabed' with letters rearranged gives 'DEBASE'.
'to' is the link.
(Other definitions for debase that I've seen before include "Lower, degrade" , "Lower in quality, reduce the value of" , "dishonour" , "Lower -- seabed (anag)" , "Lower in quality or value, corrupt" .)