Flowering shrub that meant nothing to a legendary swimmer (8)
I believe the answer is:
oleander
'flowering shrub that meant' is the definition.
'oleander' can be an answer for 'flowering shrub' (I've seen this before). I'm not certain of the remainder of the definition.
'nothing to a legendary swimmer' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'to' is a charade indicator (letters next to each other).
'a legendary swimmer' becomes 'leander' (I've seen this before. I am not sure about the 'legendary' bit.).
'o'+'leander'='OLEANDER'
Can you help me to learn more?
(Other definitions for oleander that I've seen before include "'Adorn eel, badly, with this shrub (8)'" , "Adore Len (anag.)" , "Poisonous shrub, also called rosebay" , "No dealer in evergreen shrub" , "No leader, oddly, for the flowering shrub" .)