Old newts all over the place in deserts? (4,4)

I believe the answer is:

lets down

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'deserts?' is the definition.
Although both the answer and definition are verbs in their -s form, I don't see how one could define the other.

'old newts all over the place' is the wordplay.
'all over the place' indicates anagramming the letters.
'old'+'newts'='oldnewts'
'oldnewts' anagrammed gives 'LETS DOWN'.

'in' is the link.

Can you help me to learn more?

I've seen this clue in the Irish Times and the Irish Times (Crosaire).

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