Thwart or foil a plan (9)

I believe the answer is:

frustrate

(Other definitions for frustrate that I've seen before include "Prevent from progressing" , "Put a stop to" , "'Thwart, disappoint (9)'" , "Thwart or baffle" , "Prevent (plan) from being fulfilled" .)

I've seen this clue in The Irish Times.

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