Blow from right or left initially endangering rock snake (10)
I believe the answer is:
sidewinder
'snake' is the definition.
(sidewinder is a kind of snake)
'blow from right or left initially endangering rock' is the wordplay.
I cannot quite see how this works, but
'blow' could be 'wind' and 'wind' is found in the answer.
'right' could be 'r' (common abbreviation) and 'r' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for sidewinder that I've seen before include "Rattlesnake with distinctive motion" , "Rattlesnake; misile" , "rattling creature" , "1 of 21 [SNAKES] ?" , "Rattlesnake - air-to-air missile" .)