With a leg on each side of (7)
I believe the answer is:
astride
'with a leg on each side of' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for astride that I've seen before include "on horseback" , "Extending across" , "With a leg on both sides" , "Not side saddle" , "With legs stretched apart - tirades (anag)" .)