Thesaurus.com
Dictionary.com
Definitions

mysterious

[mi-steer-ee-uhs] / mɪˈstɪər i əs /
ADJECTIVE
obscure, puzzing, suggesting a mystery
Synonyms
STRONGEST
baffling cryptic curious dark enigmatic inexplicable inscrutable magical mystical mystifying obscure perplexing puzzling secretive strange unknown weird
WEAK
abstruse alchemistic arcane astrological cabalistic covert difficult eldritch enigmatical equivocal esoteric furtive hidden impenetrable incomprehensible insoluble necromantic occult oracular recondite sphinxlike spiritual subjective symbolic transcendental uncanny unfathomable unknowable unnatural veiled
Antonyms
STRONGEST
apparent bright clear comprehendible comprehensible evident familiar intelligible known normal obvious plain regular usual visible
WEAK
public straightforward tangible unmysterious

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A British Bitcoin entrepreneur has told the BBC he is not the digital currency's mysterious inventor after a New York Times article named him as its creator.

From BBC • Apr. 8, 2026

So the Sora video-generating app was canceled, and my guess is the Atlas browser—plus a mysterious hardware device by designer diva Jony Ive—may be the next to be killed.

From The Wall Street Journal • Mar. 29, 2026

The regulatory filing also disclosed that a mysterious bidder had surfaced at the auction’s 11th hour.

From Los Angeles Times • Mar. 26, 2026

Ursula has shades of Gellar’s famous characters — Buffy’s physical ferocity, Kathryn Merteuil’s ruthless cattiness, Daphne Blake’s affinity for mysterious games — but doesn’t play to one exclusively.

From Salon • Mar. 26, 2026

I turn away from them, pretend like I’m putting on deodorant, and slip the mysterious postcard from my waistband.

From "South of Somewhere" by Kalena Miller