Definition from Wiktionary, the free dictionary
Jump to: navigation, search



From Latin fallax (deceptive). See fallacy.


fallax (plural fallaxes)

  1. (obsolete) cavillation; petty criticism
    (Can we find and add a quotation of Cranmer to this entry?)

Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.
(See the entry for fallax in
Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913.)



From fallō (I deceive) +‎ -āx (inclined to).



fallāx (genitive fallācis); third declension

  1. deceptive, deceitful
  2. fallacious, spurious


Third declension.

Number Singular Plural
Case / Gender Masc./Fem. Neuter Masc./Fem. Neuter
nominative fallāx fallācēs fallācia
genitive fallācis fallācium
dative fallācī fallācibus
accusative fallācem fallāx fallācēs fallācia
ablative fallācī fallācibus
vocative fallāx fallācēs fallācia


  • fallax in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
  • fallax in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
  • fallax in Gaffiot, Félix (1934) Dictionnaire Illustré Latin-Français, Hachette
  • Carl Meissner; Henry William Auden (1894) Latin Phrase-Book[1], London: Macmillan and Co.
    • a fallacious argument; sophism: conclusiuncula fallax or captio