Reported stream of ice (4)
I believe the answer is:
floe
'ice' is the definition.
(thesaurus)
'reported stream' is the wordplay.
'reported' indicates a 'sounds like' (homophone) clue.
'stream' becomes 'flow' (synonyms).
'flow' sounds like 'FLOE'.
'of' acts as a link.
(Other definitions for floe that I've seen before include "Broken piece of pack-ice" , "Comparatively small piece of floating ice" , "Floating flat mass of ice" , "Flat mass of sea ice" , "Part separated from a mass of ice" .)