Order: wear valid mask (4,1,4)

I believe the answer is:

draw a veil

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'mask' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'order wear valid' is the wordplay.
'order' indicates an anagram.
'wear'+'valid'='wearvalid'
'wearvalid' anagrammed gives 'DRAW A VEIL'.

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