Famous ostrich I trained (8)
I believe the answer is:
historic
'famous' is the definition.
(I've seen this before)
'ostrich i trained' is the wordplay.
'trained' indicates an anagram (to train can mean to grow something into a shape).
'ostrich'+'i'='ostrichi'
'ostrichi' anagrammed gives 'HISTORIC'.
(Other definitions for historic that I've seen before include "Momentous, noteworthy" , "remarkable" , "Of significance in the past" , "sort of present" , "Memorable" .)