To instil mortal fear, stun suspect to begin with (9)

I believe the answer is:

transfuse

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'to instil' is the definition.
Although both the answer and definition are verbs in their base form, I don't see how one could define the other.

I can't explain the remainder of the clue.

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(Other definitions for transfuse that I've seen before include "Safest run (anag.)" , "Spread throughout" .)

I've seen this clue in The Guardian.

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