Get even with travel agency management centres (6)

I believe the answer is:

avenge

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'get even' is the definition.
(I've seen this before)

I don't understand the rest of the clue.

(Other definitions for avenge that I've seen before include "Repay (a wrong)" , "Indulge in retaliation" , "Requite, repay" , "Even the score" , "Exact retribution, take satisfaction for injury" .)

I've seen this clue in The Guardian.

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