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An attempted "night cap" which inadvertently turns into two or three drinks, thus becoming a "night helmet". Can also be attributed to a "night cap" drink served with a generous and sometimes unexpected alcoholic measure - i.e. in Spain or Italy.
"Steady on with the Jack Daniels Gueseppie, that's supposed to be a nightcap, not a night helmet".
by Mat Morris September 05, 2007
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