Obtain, only to thrust out of the way! (6)
'obtain' is the definition.
(deriving is a kind of obtaining)
'only to thrust out of the way' is the wordplay.
I cannot quite see how this works, but
'way' could be 'e' (Compass direction - East) and 'e' is present in the answer.
'thrust' could be 'drive' (synonyms) and 'drive' is found in the leftover letters.
No letters remain.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for derive that I've seen before include "Get or trace from a source", "Arise (from); deduce", "Originate, come (from)", "Issue", "Originate (from something)".)