Learning by repetition (4)
I believe the answer is:
rote
'learning by repetition' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for rote that I've seen before include "By . . . . means by memory - that tore it" , "Learn by . . . . to have off by heart" , "Memorisation by repetition" , "Repetition of something to be learned" , "Repetition from memory" .)