Falterer on regular basis? Run away (4)
I believe the answer is:
flee
'run away' is the definition.
(to flee is to run away)
'falterer on regular basis?' is the wordplay.
'on regular basis?' indicates alternate letters (I've seen 'on regular basis' mean this (letters selected at regular intervals)).
The alternate letters of 'falterer' are 'FLEE'.
(Other definitions for flee that I've seen before include "rush" , "Take flight" , "Maybe escape" , "retreat" , "Turn tail" .)