On horseback (6)
'on horseback' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for mounted that I've seen before include "On horseback" , "On a steed" , "Prepared for exhibition" , "Scaled" , "Riding a horse" .)
'on horseback' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for riding that I've seen before include "Canadian constituency" , "Sitting on and controlling the movements of a horse" , "Horsemanship - once a third part of Yorkshire" , "Travelling on horseback" , "Parliamentary constituency (Canada) - former administrative district (Yorkshire)" .)