Prevail upon to spread after zero crowding (14)

I believe the answer is:

overpopulation

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'prevail upon to spread after zero crowding' is the definition.
I can't judge whether this defines the answer.

'prevail upon to spread after zero' is the wordplay.
'spread' indicates an anagram.
'after' means one lot of letters go next to another.
'zero' becomes 'O' (O resembles 0).
'prevail'+'upon'+'to'='prevailuponto'
'prevailuponto' anagrammed gives 'verpopulation'.
'verpopulation' after 'o' is 'OVERPOPULATION'.

Can you help me to learn more?

(Other definitions for overpopulation that I've seen before include "Malthusian problem" , "Excess of people in a place" .)

I've seen this clue in The Times and The Sunday Times.

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