from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun Philosophy An indivisible, impenetrable unit of substance viewed as the basic constituent element of physical reality in the metaphysics of Leibniz.
  • noun Biology A single-celled microorganism, especially a flagellate protozoan formerly classified in the taxonomic group Monadina.

from The Century Dictionary.

  • noun In metaphysics, an individual and indivisible substance.
  • noun In biology:
  • noun Any simple single-celled organism.
  • noun In zoology, specifically, a flagellate infusorian; one of the Infusoria flagellata, characterized by the possession of one or two long whip-like flagella, and generally exhibiting an endoplast and a contractile vacuole. The word in this sense is derived from the name of the genus Monas.
  • noun In chem., an element whose atoms have the lowest valence or atomicity, which valence is therefore taken as unity.
  • In chem. and biology, of or pertaining to monads; of the nature of a monad; monadi-form.

from the GNU version of the Collaborative International Dictionary of English.

  • noun An ultimate atom, or simple, unextended point; something ultimate and indivisible.
  • noun (Philos. of Leibnitz) The elementary and indestructible units which were conceived of as endowed with the power to produce all the changes they undergo, and thus determine all physical and spiritual phenomena.
  • noun (Zoöl.) One of the smallest flagellate Infusoria; esp., the species of the genus Monas, and allied genera.
  • noun (Biol.) A simple, minute organism; a primary cell, germ, or plastid.
  • noun (Chem.) An atom or radical whose valence is one, or which can combine with, be replaced by, or exchanged for, one atom of hydrogen.
  • noun (Biol.) in tectology, a unit of the first order of individuality.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun An ultimate atom, or simple, unextended point; something ultimate and indivisible.
  • noun mathematics, computing A monoid in the category of endofunctors.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun (chemistry) an atom having a valence of one
  • noun (biology) a single-celled microorganism (especially a flagellate protozoan)
  • noun a singular metaphysical entity from which material properties are said to derive


from The American Heritage® Dictionary of the English Language, 4th Edition

[Latin monas, monad-, unit, from Greek, from monos, single; see men- in Indo-European roots.]


Help support Wordnik (and make this page ad-free) by adopting the word monad.


  • The term monad is, however, generally understood in reference to the philosophy of

    The Catholic Encyclopedia, Volume 10: Mass Music-Newman 1840-1916 1913

  • Since Leibniz 'time the term monad has been used by various philosophers to designate indivisible centres of force, but as a general rule these units are not understood to possess the power of representation or perception, which is the distinguishing characteristic of the Leibnizian monad.

    The Catholic Encyclopedia, Volume 10: Mass Music-Newman 1840-1916 1913

  • Note 127: "According to Capella," Pérez-Gómez notes, "the monad is all that is good, desirable and essential — a notion that was explicitly introduced into Renaissance theology by Nicholas of Cusa in his influential work De docta ignorantia."

    Architecture and Memory: The Renaissance Studioli of Federico da Montefeltro 2008

  • Each monad is made up of 25 cities, each existing within their own sections of 40 floors.

    Robert Silverberg's "The World Inside": Overpopulation, Sex and Sensibility 2009

  • The word monad is used by the neo-Platonists to signify the One; for instance, in the letters of the Christian Platonist Synesius, God is described as the Monad of

    The Catholic Encyclopedia, Volume 10: Mass Music-Newman 1840-1916 1913

  • This second abstraction, "thrown off" by our pure self-consciousness just as the first one is "thrown off" by our pure reason, becomes therefore an intervening monad which exists midway between the monad which is pure "subject" -- if that can be called a monad at all -- and the actual individual soul which is the living reality of both these thought-projections.

    The Complex Vision John Cowper Powys 1917

  • Below this first principle are a second one, which is also called the monad, and the indefinite dyad.

    Pythagoreanism Huffman, Carl 2006

  • The monad, which is opposed to the indefinite dyad, is just one of three gods for Numenius (Fr. 11 Des Places), who here follows Moderatus to a degree.

    Pythagoreanism Huffman, Carl 2006

  • For in the numbers the infinite in the direction of reduction is not present, as the monad is the smallest; nor is the infinite in the direction of increase, for the parts number only up to the decad.

    Physics Aristotle 2002

  • In short, the monad was the keystone of Bruno's all-embracing uni - versal scheme.

    Dictionary of the History of Ideas ROBERT H. KARGON 1968


Log in or sign up to get involved in the conversation. It's quick and easy.

  • 18 listings, but not a single comment. There's some pretty interesting stuff here. Read the Wikipedia entry and discuss.

    March 30, 2009

  • He screamed monad! To all. To set the tone and start buisness.

    February 14, 2012