Not straight about Niamh's play sent out of the country (10)

I believe the answer is:

banishment

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'not straight about niamh's play sent out of the country' is the definition.
I can't judge whether this definition defines the answer.

'not straight about niamh's play' is the wordplay.
'not straight' becomes 'bent' (I've seen this before).
'about' indicates putting letters inside.
'play' indicates anagramming the letters.
'niamhs' anagrammed gives 'anishm'.
'bent' going around 'anishm' is 'BANISHMENT'.

Can you help me to learn more?

(Other definitions for banishment that I've seen before include "Expatriation" , "The exclusion of someone from a country" , "Exile" .)

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

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