enigma

noun

enig·​ma i-ˈnig-mə 

e-

1

: something hard to understand or explain

Before the Apollo program, the origin of the moon was an enigma.

—Eva Botkin-Kowacki

2

: an inscrutable or mysterious person

How frustrated profile writers sum him up: "He remains an enigma."

—The Guardian (London)

3

: an obscure speech or writing

… enlivening the meticulous realism of the scene-setting … by little enigmas and surprises … fed to the reader.

—David Lodge

Did you know?

Enigma comes from a Greek word that means "to speak in riddles." It applies to things, as well as to people, that puzzle one's mind. Egypt's ancient pyramids and quantum mechanics, for example, might be described as enigmas, as well as physicist Stephen Hawking. In these uses, the word's meaning is a figurative extension of the original "riddle" sense.

Did you know?

Are you an enigma?

A person who is described as an enigma is a bit of a mystery. You never know what that person is really thinking, or what his or her motives for doing something are. An enigma is not easily understood especially because he or she has a confusing mixture of qualities that seem to be in opposition to one another—for example, the attention-seeking but reclusive musician, or the brilliant lawyer who gets lost on the drive home from the grocery store.

The word enigma originally referred not to people but to words, and specifically to words that formed a riddle or complicated metaphor that tested the listener's or reader's alertness and cleverness. This meaning is clearly connected to the word's history. Enigma comes from a Greek word that means "to speak in riddles."

The word enigma didn't jump from referring to riddles to referring to people. In between those uses, it was (and still is) applied to things that puzzle people. Egypt's meticulously constructed Pyramids of Giza or a theory of quantum physics, for example, might be described as enigmas. In these uses, the meaning is simply a figurative extension of the original "riddle" sense.

Synonyms of enigma

• mystery

Choose the Right Synonym for enigma

mystery, problem, enigma, riddle, puzzle mean something which baffles or perplexes.

mystery applies to what cannot be fully understood by reason or less strictly to whatever resists or defies explanation.

the mystery of the stone monoliths

problem applies to a question or difficulty calling for a solution or causing concern.

problems created by high technology

enigma applies to utterance or behavior that is very difficult to interpret.

his suicide remains an enigma

riddle suggests an enigma or problem involving paradox or apparent contradiction.

the riddle of the reclusive pop star

puzzle applies to an enigma or problem that challenges ingenuity for its solution.

the thief's motives were a puzzle for the police

Examples of enigma in a Sentence

Despite the enigma of the singularity, the big bang theory is unquestionably one of the most successful ideas in the history of science. —Tom Yulsman, Astronomy, September 1999

Many scholars call it the ultimate enigma of the Nazi era, indeed perhaps of modern history: How did the Holocaust happen? And why in Germany? —Ralph Blumenthal, New York Times, 10 Jan. 1998

Indeed, the bond that in every individual connects the physiological life and the psychic life—or better the relation existing between the contingence of an individual and the free spirit that assumes it—is the deepest enigma implied in the condition of being human, and this enigma is presented in its most disturbing form in woman. —Simone de Beauvoir, translated and edited by H. M. Parshley, The Second Sex, 1953

To his friends, he was always something of an enigma.

one of the great enigmas of our time

Recent Examples on the Web

Further enigmas can be found elsewhere on public lands, including within state parks, recreational areas, and more. —Mike Bezemek, Outside, 29 Oct. 2025

Soho House has always existed as something of an enigma to me. —Rachel Desantis, PEOPLE, 29 Oct. 2025

Gorman reunites with Okuno after playing a memorable enigma of a movie monster in her debut feature, Watcher. —Matt Grobar, Deadline, 23 Oct. 2025

If anything, the ongoing questions around the strange journey of the Lizard King’s bust only add to the enigma. —David Kushner, Rolling Stone, 20 Oct. 2025

Word History

Etymology

Latin aenigma, from Greek ainigmat-, ainigma, from ainissesthai to speak in riddles, from ainos fable

First Known Use

1539, in the meaning defined at sense 3

Rhymes for enigma

• kerygma
• sigma
• stigma

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Kids Definition

enigma

noun

enig·​ma i-ˈnig-mə 

: something hard to understand or explain

enigmatic

ˌen-ig-ˈmat-ik

ˌē-nig-

adjective

also enigmatical

-ˈmat-i-kəl

enigmatically

-i-k(ə-)lē

adverb