• WordNet 3.6
    • v countersign add one's signature to after another's to attest authenticity "You must countersign on this line of the contract"
    • n countersign a second confirming signature endorsing a document already signed
    • n countersign a secret word or phrase known only to a restricted group "he forgot the password"
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Webster's Revised Unabridged Dictionary
    • Countersign (Mil) A private signal, word, or phrase, which must be given in order to pass a sentry; a watchword.
    • Countersign The signature of a secretary or other officer to a writing signed by a principal or superior, to attest its authenticity.
    • v. t Countersign To sign on the opposite side of (an instrument or writing); hence, to sign in addition to the signature of a principal or superior, in order to attest the authenticity of a writing.
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Century Dictionary and Cyclopedia
    • countersign To sign opposite to another signature; sign additionally; superadd one's signature to by way of authentication, attestation, or confirmation: as, charters signed by a king are countersigned by a secretary.
    • countersign Figuratively, to attest in any way; confirm; corroborate.
    • n countersign A private signal, in the form of a word, phrase, or number, given to soldiers on guard, with orders to let no one pass unless he first gives that sign; a military watchword.
    • n countersign The signature of a secretary or other subordinate officer to a writing signed by the principal or superior, to attest its authenticity; a counter-signature. Synonyms See. parole, 3.
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Chambers's Twentieth Century Dictionary
    • v.t Countersign to sign on the opposite side of a writing: to sign in addition to the signature of a superior, to attest the authenticity of a writing
    • ns Countersign a military private sign or word, which must be given in order to pass a sentry: a counter-signature
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Webster's Revised Unabridged Dictionary
Counter-, + sign,: cf. F. contresigner,
Chambers's Twentieth Century Dictionary
Fr.,—L. contra, against.


In literature:

I see the order is countersigned by La Barre.
"Beyond the Frontier" by Randall Parrish
And then the portraits are both signed and countersigned.
"The Works of Robert Louis Stevenson - Swanston Edition" by Robert Louis Stevenson
But the warrant, madam, was countersigned.
"The Works of Robert Louis Stevenson - Swanston Edition Vol. 7 (of 25)" by Robert Louis Stevenson
The winners in the drawing must be prepared to have their tickets countersigned on the spot.
"Gold" by Stewart White
Each signature must be countersigned by the signatory's own Bishop, who thus guarantees the Clergyman's moral fitness to certify.
"The Church: Her Books and Her Sacraments" by E. E. Holmes
The countersign was "Jemmapes and Fleurus," this struck me at once, I had not heard this countersign since 1813.
"Waterloo" by Émile Erckmann
He also must countersign the receipts.
"Timar's Two Worlds" by Mór Jókai
The Arabs themselves were supposed to be sufficiently intelligent to tell a friend from a foe without requiring any countersign.
"The Boy Slaves" by Mayne Reid
The sentinel challenged, and Silent went forward and gave the countersign.
"Uncle Daniel's Story Of "Tom" Anderson And Twenty Great Battles" by John McElroy
He hain't got the countersign; shall I pass him?
"Si Klegg, Book 1 (of 6) His Transformation From A Raw Recruit To A Veteran" by John McElroy

In poetry:

We ask to-day no countersign,
No party names we own;
Unlabelled, individual,
We bring ourselves alone.
"June On The Merrimac" by John Greenleaf Whittier
Thy gates are shut to hardiest will,
Thy countersign of long-lost speech,--
Those fountained courts, those chambers still,
Fronting Time's far East, who shall reach?
"The Foot-Path" by James Russell Lowell
Well to suffer is divine;
Pass the watchword down the line,
Pass the countersign: "Endure."
Not to him who rashly dares,
But to him who nobly bears,
Is the victor's garland sure.
"Burial of Barber" by John Greenleaf Whittier
For presently, O soldiers, we too camp in our place in the bivouac-
camps of green;
But we need not provide for outposts, nor word for the countersign,
Nor drummer to beat the morning drum.
"Camps Of Green" by Walt Whitman
Then a health and a welcome to woman once more!
She brings us a passport that laughs at our door;
It is written on crimson—its letters are pearls—
It is countersigned Nature—so, room for the Girls!
"A Health To Dear Woman" by John Pierpont
Some won the world's homage, their names we hold dear,--
But Friendship, not Fame, is the countersign here;
Make room by the conqueror crowned in the strife
For the comrade that limps from the battle of life!
"My Annual" by Oliver Wendell Holmes