Irish writer's novel, most inferior part sent up (8)
I believe the answer is:
sheridan
'irish writer's' is the definition.
(Richard Brinsley Sheridan)
'novel most inferior part sent up' is the wordplay.
'novel' becomes 'she' (I've seen this before).
'most inferior part' becomes 'nadir'.
'sent up' says the letters should be written backwards.
'nadir' written backwards gives 'ridan'.
'she'+'ridan'='SHERIDAN'
(Other definitions for sheridan that I've seen before include "Richard Brinsley . . . . . . . . was a great 18th century Irish playwright" , "Richard Brinsley ........, Anglo-Irish author of ` `The School for Scandal' '" , "Irish playwright (The Rivals)" , "Who scandalised the educational establishment?" , "Irish dramatist" .)