red line

noun

1. Ice Hockey.,  a line of the color red that is parallel to and equidistant from the goal lines and divides the rink in half.

2. a limit, point, or boundary beyond which one may not go without incurring negative consequences.

   The use of chemical weapons is a red line, which, if crossed, could trigger military action.

red line

noun

1. a point beyond which a person or group is not prepared to negotiate

Word History and Origins

Origin of red line¹

First recorded in 1960–65

Example Sentences

However, Defence Minister Katz said Hamas had crossed "a bright red line" by launching an attack on Israeli soldiers in Gaza on Tuesday.

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The red line represents the best-fit trendline, and notice that it is nearly flat, meaning that there is no significant trend.

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“I am very worried, because it means that decisions could be made that go against Israel’s red lines.”

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Indian negotiators have their red lines—the farm lobby is even more powerful in New Delhi than in Washington—but negotiators on both sides say a deal is within reach.

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However, Moscow's "red line" on Western missiles has already been crossed without any clear consequences.

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