In Ireland, a naggin is a 200ml bottle of spirits. Spirits are commonly sold in this size in off licences, especially independent (non-chain) shops.
Etymology According to the Oxford English Dictionary, naggin is a variant of noggin, a word of uncertain origin recorded from the seventeenth century and meaning a small quantity of alcohol, usually one gill (). Tomás S. Ó Máille derives it from the Irish naigín, cnaigín, a small wooden pail with a capacity of two glasses.Tomás S. Ó Máille, Seanfhocla Chonnacht, Cois Life, 2010, p. 368
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