Old people I notice close by, within hearing (5)

I believe the answer is:

iceni

'old people' is the definition.
(ancient tribe of Britain)

I don't understand the remainder of the clue.

(Other definitions for iceni that I've seen before include "Old people" , "Ancient Brits" , "Ancient British tribe" , "Ancient tribesmen" , "Old tribe" .)

I've seen this clue in The Times.

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