Prize rams in new enterprises (5-3)

I believe the answer is:

start-ups

'new enterprises' is the definition.
(new businesses)

'prize rams' is the wordplay.
'prize' becomes 'star' (both can mean excellent or well-regarded).
'rams' becomes 'tups' ('tup' can be a synonym of 'ram').
'star'+'tups'='START-UPS'

'in' acts as a link.

I've seen this clue in The Guardian.

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