Regularly using coercion, force on border flower (7)
I believe the answer is:
orinoco
'border flower' is the definition.
(a border river or, whimsically, a border flow-er)
'regularly using coercion force on' is the wordplay.
'regularly using' means one should take alternating letters.
'coercion'+'force'+'on'='coercionforceon'
The alternate letters of 'coercionforceon' are 'ORINOCO'.
(Other definitions for orinoco that I've seen before include "River of South America" , "moves between South American banks" , "Great river flowing through Venezuela to Atlantic" , "South-American river" , "large flow of water" .)