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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.

The mysterious arson fires in a Hollywood neighborhood started small.

From Los Angeles Times • Apr. 1, 2026

After all, Vance had really just wanted to highlight religion, it would have made a little more sense to portray mysterious flying objects as angels, not demons.

From Salon • Apr. 1, 2026

Yet tourists might find themselves entirely alone at Cromeleque dos Almendres which along with the smaller and less-visited Cromeleque de Vale Maria do Meio are mysterious mini-Stonehenge circles of planted stone monoliths.

From The Wall Street Journal • Mar. 27, 2026

Researchers have uncovered how a mysterious ion channel helps cells break down waste, opening new possibilities for treating Parkinson's disease.

From Science Daily • Mar. 26, 2026

We are good German children who have been stricken with a mysterious ailment.

From "Code Name Kingfisher" by Liz Kessler

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.