perfidiousness

English

Etymology tree

English perfidious

Proto-Germanic *-in-

Proto-Indo-European *-h₂

Proto-Indo-European *-éh₂

Proto-Indo-European *-yéti

Proto-Indo-European *-eh₂yéti

Proto-Indo-European *-h₂ti

Proto-Germanic *-ōną

Proto-Germanic *-inōną

Proto-Indo-European *-dyé-

Proto-Germanic *-atjaną

Proto-Indo-European *-tus

Proto-Germanic *-þuz

Proto-Germanic *-assuz

Proto-Germanic *-inassuz

Proto-West Germanic *-nassī

Old English -nes

Middle English -nesse

English -ness

English perfidiousness

perfidiousness (usually uncountable, plural perfidiousnesses)

(rare) Unfaithfulness; deceitfulness; perfidy.
Synonyms: double-dealing, treachery, treacherousness; see also Thesaurus:betrayal
- 1781, Samuel Johnson, “Addison”, in Lives of the Poets:
  Not only Cato is vanquished by Caesar, but the treachery and perfidiousness of Syphax prevail over the honest simplicity and the credulity of Juba.

Noah Webster (1828), “perfidiousness”, in An American Dictionary of the English Language: […], volume II (J–Z), New York, N.Y.: […] S. Converse; printed by Hezekiah Howe […], →OCLC.
“perfidiousness”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.
“perfidiousness”, in Dictionary.com Unabridged, Dictionary.com, LLC, 1995–present.