Almost incredible English fiction (4)
I believe the answer is:
tale
'fiction' is the definition.
(thesaurus)
'almost incredible english' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'incredible' becomes 'tall' (as in a tall tale).
'english' becomes 'e' (abbreviation).
'tall' with its final letter taken off is 'tal'.
'tal'+'e'='TALE'
(Other definitions for tale that I've seen before include "Report" , "Old wives' recital?" , "Story or anecdote" , "See 20" , "Anecdotal narrative" .)