Run from large snake (6)
I believe the answer is:
ladder
'run' is the definition.
('ladder' can be a synonym of 'run')
'large snake' is the wordplay.
'large' becomes 'l'.
'snake' becomes 'adder' (adder is a kind of snake).
'l'+'adder'='LADDER'
'from' is the link.
(Other definitions for ladder that I've seen before include "Climbing structure" , "Scaling device" , "Companionway" , "Run in stockings" , "Climbing frame; damage tights" .)