• WordNet 3.6
    • adj perfidious tending to betray; especially having a treacherous character as attributed to the Carthaginians by the Romans "Punic faith","the perfidious Judas","the fiercest and most treacherous of foes","treacherous intrigues"
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Webster's Revised Unabridged Dictionary
    • Perfidious Guilty of perfidy; violating good faith or vows; false to trust or confidence reposed; teacherous; faithless; as, a perfidious friend.
    • Perfidious Involving, or characterized by, perfidy. "Involved in this perfidious fraud."
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Century Dictionary and Cyclopedia
    • perfidious Faithless; basely treacherous; false-hearted.
    • perfidious Proceeding from or characterized by perfidy or base treachery; false: as, a perfidious act. Synonyms Unfaithful, Faithless, Treacherous, Perfidious. Unfaithful represents negatively the meaning that is common to these words, but it especially means a lack of fidelity to trust or duty, a failure to perform what is due, however much may be implied in that. Faithless is negative in form, but positive in sense; the faithless man does something which is a breach of faith; the sleeping sentinel is unfaithful; the deserter is faithless. Treachery and perfidy are kinds of faithlessness. The treacherous man either betrays the confidence that is reposed in him, or lures another on to harm by deceitful appearances: as, the treacherous signals of the wrecker. The perfidious man carries treachery to the basest extreme; he betrays acknowledged and accepted obligations, and even the most sacred relationships and claims: as, Benedict Arnold and Judas are types of perfidy.
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Chambers's Twentieth Century Dictionary
    • adj Perfidious per-fid′i-us faithless: unfaithful: basely violating trust: treacherous
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Perfidious Albion - England is known to some as perfidious Albion, implying that it is not trustworthy in its dealings with foreigners.


Webster's Revised Unabridged Dictionary
L. perfidious,
Chambers's Twentieth Century Dictionary
L. perfidiosusperfidia, faithlessness.


In literature:

The unutterable perfidy of man!
"Septimus" by William J. Locke
And you, perfidious soldiers of Hassan, what demon has moved you to commit so great an outrage?
"The Exemplary Novels of Cervantes" by Miguel de Cervantes Saavedra
It was only since the discovery of Lablache's perfidy that "Lord" Bill had understood what living meant.
"The Story of the Foss River Ranch" by Ridgwell Cullum
He urges him to open it; to desert the perfidious city, and to adopt Pisa's cause.
"A Handbook to the Works of Browning (6th ed.)" by Mrs. Sutherland Orr
She will suffer cruelty, penury, insults, before she behaves so shamefully, so perfidiously.
"The Honorable Peter Stirling and What People Thought of Him" by Paul Leicester Ford
It worked by means of treachery, covetousness, perfidy, and the perversion of all natural affections.
"The Land-War In Ireland (1870)" by James Godkin
I forgot the former lessons I had learned from her perfidy.
"Dorothy Vernon of Haddon Hall" by Charles Major
He surpasses all beings in those arts called Cunning and Perfidy.
"Ten Great Religions" by James Freeman Clarke
He surpasses all beings in those arts called Cunning and Perfidy.
"The Elder Eddas of Saemund Sigfusson; and the Younger Eddas of Snorre Sturleson" by Saemund Sigfusson and Snorre Sturleson
Couthon, have you not pronounced him perjured, perfidious, and unfit to live?
"Blackwood's Edinburgh Magazine, No. 341, March, 1844, Vol. 55" by Various
It was a sordid story of woman's perfidy, twice told.
"The Wings of the Morning" by Louis Tracy
But the Muses shall cease from their ancient strains, from celebrating our perfidy.
"The Tragedies of Euripides, Volume I." by Euripides
It was a repetition of the perfidy over the Treaty of Limerick a century before.
"The Framework of Home Rule" by Erskine Childers
It was that fatal and perfidious bark, Built in th' eclipse, and rigg'd with curses dark.
"Handy Dictionary of Poetical Quotations" by Various
It was white rose, a perfume forever associated with the perfidious Lady Hortense!
"The Honorable Percival" by Alice Hegan Rice
Nothing approaching the perfidy of it could happen in the present age.
"The Tragedy of St. Helena" by Walter Runciman
The two victims of this perfidy were immediately buried upon the spot where they fell.
"The Empire of Russia" by John S. C. Abbott
These people are in general very industrious, but covetous, false, and perfidious.
"A General History and Collection of Voyages and Travels, Volume 11" by Robert Kerr
The monarch, you will tell me, was guilty of perfidy and perjury.
"The Prose Works of William Wordsworth" by William Wordsworth
Equally infamous it was, that summary chastisement was not inflicted upon the perfidious court of Kandy.
"Blackwood's Edinburgh Magazine, Volume 54, No. 337, November, 1843" by Various

In poetry:

And envy is always envy,
Though called by a foreign name,
And perfidy, greed, and malice
Are everywhere the same.
"The Postern Gate" by John Lawson Stoddard
But if you spurn us, then we shall not mourn.
We too can reckon perfidy no crime,
And countless generations yet unborn
Shall curse your memory till the end of time.
"The Scythians" by Aleksandr Aleksandrovich Blok
"Let her who seal'd a lover's fate, endure
The sharpest pressure of deserv'd distress;
'Twere added perfidy to seek a cure,
And, stain'd with falsehood, wish to suffer less.
"Euphelia" by Helen Maria Williams
Here in the crown's, our king and country's right,
We, for our lands, our goods, and nation, fight
With a perfidious and invet'rate foe,
That always seeks this kingdom's overthrow.
"The Soldier's Prayer" by Rees Prichard
Thus may the nymph, whene'er she spreads the fan,
In his true colours view perfidious man,
Pleas'd with her virgin state in forests rove,
And never trust the dangerous hopes of love.
"The Fan : A Poem. Book II." by John Gay
Why leave the wretch thy perfidy hath made.
To journey cheerless through the world's wide waste?
Say, why so soon does all thy kindness fade.
And doom me, thus, affliction's cup to taste?
"To Thaddeus" by Thomas Gent

In news:

Intent on blaming the cold war simply on Soviet perfidy, John Lewis Gaddis does a disservice to the subject of his biography—and to his readers.
Peanuts, Cracker Jacks, perfidy and laughs.
Murder, mayhem and misogyny passion, perfidy and pathos fantasy, fraud and pheromones.
Three women who helped a Puyallup banker become Pierce County's king of bad mortgage loans learned Wednesday the price of their perfidy.
There's just so much press attention the Arab world can receive before even obsessives like me begin to tire of its frenzy, pitilessness, and perfidy.
So how did the telegram end up in the hands of the British, who were quite happy to pass it to the United States to illustrate German perfidy.
" cried out General Washington when he discovered his friend's "villainous perfidy.".