Fixed so as not to give way (6)
I believe the answer is:
secure
'fixed so as not to give way' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for secure that I've seen before include "Fix; safe" , "Reliable; firmly fixed" , "Safe and well-protected" , "Free from danger and financially sound" , "Peg" .)