Green’s Dictionary of Slang

nook n.

[ety. unknown]

a penny.

[UK]J. Curtis Gilt Kid 203: There’s others what flogs them round the spikes at three nooks an ounce.
[UK]J. Curtis They Drive by Night 17: ‘Here y’are, mister. ’Spress. One penny.’ ‘You’ll get some bleeding nooks.’.
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