One on raft floating around much of day (9)
I believe the answer is:
afternoon
'much of day' is the definition.
'one on raft floating' is the wordplay.
'floating' indicates anagramming the letters (float can mean fluctuate or oscillate).
'one'+'on'+'raft'='oneonraft'
'oneonraft' is an anagram of 'AFTERNOON'.
'around' is the link.
(Other definitions for afternoon that I've seen before include "Between noon and evening" , "Period between morning and evening" , "No ante for this part of the day" , "time for tea" , "Post midday" .)