Said set of photographs was not returned to university (9)

I believe the answer is:

princeton

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'to university' is the definition.
(Princeton University is an example)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for princeton that I've seen before include "Member of the 11 in New Jersey" , "Early US university" , "American university" , "where War of Independence battle was fought?" , "US ivy league university" .)

I've seen this clue in The Irish Times.

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