Speech from Horatio Nelson (7)
I believe the answer is:
oration
'speech' is the definition.
(oration is a kind of speech)
'from horatio nelson' is the wordplay.
'from' indicates the answer is hidden within the clue.
'ORATION' can be found hidden inside 'horatio nelson'.
(Other definitions for oration that I've seen before include "An eloquent speech" , "Ontario (anag)" , "words" , "A formal or public speech" , "Making a speech" .)