Go surreptitiously like a rattle snake (5)
I believe the answer is:
sneak
'go surreptitiously' is the definition.
Both the answer and definition are adjectives. Perhaps you can see a link between them that I don't see?
'a rattle snake' is the wordplay.
'a rattle' indicates anagramming the letters.
'snake' is an anagram of 'SNEAK'.
'like' acts as a link.
Can you help me to learn more?
(Other definitions for sneak that I've seen before include "In school, tell tales" , "Cringe" , "To go stealthily" , "Go furtively and tell tales" , "thief" .)