Possibly shore up a legendary character (7)
I believe the answer is:
orpheus
'a legendary character' is the definition.
The definition suggests a singular noun which matches the answer.
'possibly shore up' is the wordplay.
'possibly' indicates anagramming the letters.
'shore'+'up'='shoreup'
'shoreup' with letters rearranged gives 'ORPHEUS'.
Can you help me to learn more?
(Other definitions for orpheus that I've seen before include "One who lost his wife" , "In Greek myth he followed his wife Eurydice into the underworld" , "In Greek mythology, he went to Hades to get Eurydice back but failed" , "Taj Mahal city" , "musician inspiring many" .)