union jack

noun

1. a jack consisting of the union of a national flag or ensign, as the U.S. jack, which has the white stars and blue field of the union of the U.S. national flag.

2. (often initial capital letter),  the British national flag.

3. any flag the overall design of which is a union.

Union Jack

noun

1. a common name for Union flag

2. (often not capitals) a national flag flown at the jackstaff of a vessel

Word History and Origins

Origin of union jack¹

First recorded in 1665–75

Example Sentences

The Union Jack waved in the night sky Thursday from one of the tallest heights of New York City.

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Some union jack and St George's flags, put up along streets since the summer, are set to be taken down by a Reform UK-led council.

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I checked into my room at the Hard Rock Hotel and Casino—a resort famous for exhibiting a Union Jack minidress that had once belonged to Ginger Spice—and quickly realized that, outside of a couple of perfunctory interviews with catatonic teens, I didn’t have much to do with myself.

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A growing number of St George's and union jack flags have appeared across England in recent months.

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A stroll beneath palm trees through a serene park led to a statue of Sir Stamford Raffles on the spot where he planted the Union Jack in 1819, starting Singapore’s rise from a fishing village to a strategic port in the British Empire.

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