Remarkably, it can be either the front or back of the horse (3)
I believe the answer is:
gee
'back of the horse' is the definition.
The answer and definition can be both to do with motion as well as being verbs in their base form.
Maybe they are linked in a way I don't understand?
'remarkably it can be either the front' is the wordplay.
I cannot quite understand how this works, but
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is located in the answer.
The remaining letters 'ge' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'or' acts as a link.
Can you help me to learn more?
(Other definitions for gee that I've seen before include "Word of encouragement to a horse" , "Gosh" , "American exclamation" , "Mild expression of surprise, may go before whiz" , "G" .)