invisible ink

[in-viz-uh-buhl ingk]

noun

1. a fluid for producing writing that is invisible until brought out by heat, chemicals, etc.

invisible ink

noun

1. a liquid used for writing that does not become visible until it has been treated with chemicals, heat, ultraviolet light, etc

Word History and Origins

Origin of invisible ink¹

First recorded in 1675–85

Example Sentences

Then the justices pitch a fit when the courts below don’t understand how to apply these orders written in invisible ink.

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In another, attributed to Aeneas the Tactician, a message hides dots of invisible ink over certain letters, which spell out the true message.

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Meanwhile, Nina has always lived as if in invisible ink.

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Dasch's handkerchief held the names of the saboteurs' contacts in America, written in invisible ink.

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They were taught how to make more invisible ink using things like aspirin and Ex-Lax.

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