Universal senior service vessel (3)

I believe the answer is:

urn

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'service vessel' is the definition.
(I've seen this in another clue)

'universal senior' is the wordplay.
'universal' becomes 'u'.
'senior' becomes 'rn' (I can't justify this - if you can you should give a lot more credence to this answer).
'u'+'rn'='URN'

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(Other definitions for urn that I've seen before include "A large vase as for human ashes" , "Vase with handles" , "Vessel for making hot drinks" , "Vase; tea vessel" , "Vessel for tea or ashes" .)

I've seen this clue in The Telegraph.

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