North Europeans, quietly abandoned in East European pass (6)
I believe the answer is:
elapse
'pass' is the definition.
(I know that pass can be written as elapse)
'north europeans quietly abandoned in east european' is the wordplay.
'north europeans' becomes 'Lapps' (people from Lapland).
'quietly' becomes 'p' (p for piano and quiet).
'abandoned' is a deletion indicator.
'in' means one lot of letters goes inside another.
'east european' becomes 'EE' (abbreviation).
'lapps' with 'p' taken away is 'laps'.
'laps' inserted within 'ee' is 'ELAPSE'.
(Other definitions for elapse that I've seen before include "run by" , "Slip away" , "Go by - pass away" , "'Pass by, as time (6)'" , "Pass away - asleep (anag)" .)