A spring swarm (6)

I believe the answer is:

abound

'swarm' is the definition.
(thesaurus)

'a spring' is the wordplay.
'spring' becomes 'bound' (bounding is a kind of springing).
'a'+'bound'='ABOUND'

(Other definitions for abound that I've seen before include "Be plentiful, exist in great quantities" , "Have riches perhaps" , "Be plentiful, swarm" , "flow" , "flourish" .)

I've seen this clue in The Telegraph.

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