1 definition by Lord Leverhulme

Commonly used but incorrect name for the Union Flag of the United Kingdom.

It should only be called the Union Jack when being flown at sea.

When flying from a flagpole on land "Union Flag"

When flying from part of a boat at sea "Union Jack"
Yank tourist "Ooooh look, the Union Jack".

Infinitely more intelligent Brit "Pillock, it's called the Union Flag".
by Lord Leverhulme December 7, 2006
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