dichotomy

noun

di·​chot·​o·​my dī-ˈkä-tə-mē 

 also  də-

plural dichotomies

1

: a division into two especially mutually exclusive or contradictory groups or entities

the dichotomy between theory and practice

also : the process or practice of making such a division

dichotomy of the population into two opposed classes

2

: something with seemingly contradictory qualities

it's a dichotomy, this opulent Ritz-style luxury in a place that fronts on a boat harbor

—Jean T. Barrett

3

: the phase of the moon or an inferior planet in which half its disk appears illuminated

4

a

: bifurcation

especially : repeated bifurcation (as of a plant's stem)

b

: a system of branching in which the main axis forks repeatedly into two branches

c

: branching of an ancestral line into two equal diverging branches

Did you know?

Dichotomy and False Dichotomy

The two most commonly used senses of dichotomy are easily (and often) confused. The older one refers to the division of something into two groups that often are mutually exclusive or contradictory (as in “the dichotomy between good and evil”). Like trichotomy (meaning “division into three parts”), this sense denotes separation into different elements, but it adds the connotation of oppositeness. The newer sense of dichotomy denotes a thing that appears to have contradictory qualities, such as a lemonade stand found in a war zone. Dichotomy is frequently found in the company of the word false; a false dichotomy is a kind of fallacy in which one is given only two choices when in fact other options are available.

Synonyms

• contradiction
• incongruity
• paradox

Examples of dichotomy in a Sentence

The amusing spectacle of the recent presidential vote in Florida should remind us of the persistence of the federal-state dichotomy. —Eugene Genovese, Atlantic, March 2001

At the close of this millennium, the favored dichotomy features a supposed battle called "the science wars." —Stephen Jay Gould, Science, 14 Jan. 2000

… to insist on its being either symbol or fact is to dwell needlessly on a false dichotomy. —Simon Schama, The Embarrassment of Riches, 1988

… the Inuit concept of their environment was centred around the dichotomy between land and sea. —Ian Hodder, Reading the Past, 1986

Her essay discusses the dichotomy between good and evil in the author's novels.

her outfit is a sartorial dichotomy: an elegant gown and ratty old tennis shoes

Recent Examples on the Web

The fear that optimizing for performance will dilute brands’ authenticity is a false dichotomy. —Alex Khassa, Forbes.com, 28 Apr. 2025

Sinners also offers a contemporary look into this racial dichotomy by subtly addressing the one-drop rule — a 1662 legal doctrine that declared anyone with any Black ancestry, regardless of how small, to be considered African American. —Melanie Curry, Refinery29, 19 Apr. 2025

The new category of galaxies would be the third, falling outside the usual neat dichotomy of young, actively star-forming blue galaxies and their older, inactive red counterparts. —David Faris, MSNBC Newsweek, 11 Apr. 2025

This difference, or dichotomy, between the water abundance in the mantle on the farside compared to the nearside of the moon is just one more thing to add to the list of differences between the two hemispheres. —Keith Cooper, Space.com, 9 Apr. 2025

Word History

Etymology

borrowed from New Latin dichotomia, borrowed from Greek dichotomía "division into two parts (of the moon, in logic), bisection," from dichótomos "cut in half, dichotomous" + -ia -ia entry 1

First Known Use

1588, in the meaning defined at sense 1

Rhymes for dichotomy

• craniotomy
• lithotomy
• phlebotomy
• tenotomy
• vagotomy
• episiotomy
• laparotomy
• osteotomy
• thoracotomy
• tracheotomy
• ovariotomy

Kids Definition

dichotomy

noun

di·​chot·​o·​my -mē 

plural dichotomies

: a division into or distinction between two groups that differ greatly

the dichotomy between good and evil

Medical Definition

dichotomy

noun

di·​chot·​o·​my

dī-ˈkät-ə-mē also də-

plural dichotomies

: a division or forking into branches

especially : repeated bifurcation