sympathetic ink

American  

[sim-puh-thet-ik ingk] / ˌsɪm pəˈθɛt ɪk ˈɪŋk /

noun

1. invisible ink.

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sympathetic ink British  

noun

1. another term for invisible ink

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Etymology

Origin of sympathetic ink

First recorded in 1715–25

Example Sentences

See Examples For:

sympathetic ink

But this was only a blind; the real letters were written in cipher, with sympathetic ink.

From Mr. Fortescue An Andean Romance by Westall, William

"Ah, sympathetic ink," exclaimed John; "well, we will see."

From Andreas Hofer by Mühlbach, L. (Luise)

We have heard of the use of sympathetic ink in this country.

From The Better Germany in War Time Being some Facts towards Fellowship by Picton, Harold W. (Harold Williams)

Cobalt, dissolved in aqua regia, makes an excellent sympathetic ink, appearing green when held to the fire, and disappearing when cold, unless it has been heated too much, when it burns the paper.

From Heads of Lectures on a Course of Experimental Philosophy: Particularly Including Chemistry by Priestley, Joseph

The first page looked as if it had been written over with some sort of sympathetic ink; but not a word could be deciphered.

From Saxe Holm's Stories by Jackson, Helen Hunt