Similar snake oil taken from devious boy (5)
I believe the answer is:
alike
'similar' is the definition.
(synonyms)
'snake oil taken from devious boy' is the wordplay.
I cannot quite see how this works, but
'from' could be 'e' (I've seen this in other clues) and 'e' is found in the answer.
'boy' could be 'ali' and 'ali' is found within the answer.
A single letter 'k' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for alike that I've seen before include "In a similar way" , "twins, perhaps" , "Equally" , "possessing similar characteristics" , "Similar, analogous" .)