未知の定義と意味 - メリアム・ウェブスター

UNKNOWN Definition & Meaning - Merriam-Webster Est. 1828 Dictionary Definition adjective noun adjective 2 adjective noun Synonyms Example Sentences Word History Phrases Containing Rhymes Entries Near Related Articles Cite this Entry Citation Kids Definition Kids More from M-W Show more Show more Citation Kids More from M-W Save Word To save this word, you'll need to log in. Log In unknown 1 of 2 adjective un·​known ˌən-ˈnōn Synonyms of unknown Simple Definition A Simple Definition is available from our Learner's Dictionary to help you understand the meaning faster. 1 a : not known It was a world and life, a way of being, utterly unknown to me. — Avi An unknown number of cases go unreported. For some unknown reason , the computer crashed. b : not well-known an unknown writer/artist When he left, he had been unknown . Now he was famous. — E. B. White 2 : having an unknown value an unknown quantity unknown 2 of 2 noun 1 a : one that is not known or not well-known especially : a person who is little known (as to the public) The director cast an unknown in the lead role. b the unknown : a place, situation, or thing that is not known or understood explorers venturing into the unknown c : something that is not known or not yet discovered There are too many unknowns to go forward with the project. 2 a : a symbol (such as x, y , or z ) in a mathematical equation representing an unknown quantity b : a specimen (as of bacteria or mixed chemicals) required to be identified as an exercise in appropriate laboratory techniques Synonyms of unknown Relevance Adjective unfamiliar unbeknownst See All Synonyms & Antonyms in Thesaurus Examples of unknown in a Sentence Adjective a disease of unknown cause Much remains unknown about his early life. Her music was previously unknown outside of Asia. An unknown number of cases go unreported. The victim's attacker was unknown to her. For some unknown reason , my computer crashed. a book of unknown poems Noun explorers venturing off into the unknown A fear of the unknown kept her from changing jobs. The director cast an unknown in the lead role. We're facing too many unknowns . See More Recent Examples on the Web Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback . Adjective The Trinity fire, which started May 1 in Phelan, burned 19 acres with no structures damaged, though the blaze destroyed an unknown number of Joshua trees. — Blanca Begert, Los Angeles Times , 3 May 2026 Pitching was expected to be the Hurricanes’ weak point this season, with their bullpen being a complete unknown entering the campaign. — Jordan McPherson, Miami Herald , 3 May 2026 Noun Lilacs and the endless wonders of spring gently remove the asterisk from our desire for change, reminding us to take solace in the familiar while welcoming all that the unknown may bring. — Emily Leahy, Hartford Courant , 3 May 2026 San Antonio featured four regulars –De’Aaron Fox, Stephon Castle, Devin Vassell and Dylan Harper — and yet Denver’s unknowns refused to flinch. — Troy Renck, Denver Post , 1 May 2026 See All Example Sentences for unknown Word History First Known Use Adjective before the 12th century, in the meaning defined at sense 1a Noun 14th century, in the meaning defined at sense 1a Time Traveler The first known use of unknown was before the 12th century See more words from the same century Phrases Containing unknown big unknown fear of the unknown of unknown origin the unknown unknown quantity unknown to Rhymes for unknown alone atone backbone bemoan bluestone breastbone brownstone capstone cheekbone condone curbstone cyclone See All Rhymes for unknown Browse Nearby Words unknowledgeable unknown unknown quantity See all Nearby Words Articles Related to unknown Adjectives that Look Like Nouns There is a ruthless efficiency in the editing of dictionaries Cite this Entry Style MLA Chicago APA Merriam-Webster “Unknown.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/unknown. Accessed 6 May. 2026. Copy Citation Kids Definition unknown 1 of 2 adjective un·​known ˌən-ˈnōn : not known also : having an unknown value an unknown quantity unknown 2 of 2 noun 1 : something that is unknown 2 : a symbol (as x, y, or z ) representing a quantity whose value is unknown an equation with two unknowns More from Merriam-Webster on unknown Nglish: Translation of unknown for Spanish Speakers Last Updated: 5 May 2026 - Updated example sentences Love words? Need even more definitions? Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free! Merriam-Webster unabridged More from Merriam-Webster Word of the Day flamboyant See Definitions and Examples » Get Word of the Day daily email! Popular in Grammar & Usage See More More Commonly Mispronounced Words Regarding the Incorrect Use of 'Decimate' 5 Verbal Slip Ups and Language Mistakes Is that lie 'bald-faced' or 'bold-faced'? 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