adverb or adjective
lo·​co | \ ˈlō-(ˌ)kō How to pronounce loco (audio) \

Definition of loco

 (Entry 1 of 4)

: in the register as written used as a direction in music


plural locos or locoes

Definition of loco (Entry 2 of 4)


locoed; locoing; locos

Definition of loco (Entry 3 of 4)

transitive verb

1 : to poison with locoweed
2 : to make frenzied or crazy

Definition of loco (Entry 4 of 4)

: mentally disordered : crazy, frenzied

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Examples of loco in a Sentence

Verb years of living alone had clearly locoed the old rancher Adjective The crowd went loco when she walked out on the stage. He's not just weird, he's positively loco.
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Recent Examples on the Web: Noun The company also offers spam and teriyaki versions of loco moco. Laura Latzko, azcentral, "Arizona Aloha Festival: The food, dances and everything else to see," 10 Mar. 2020 Mom’s fideo loco, Paula’s chicken pot pie, Addie’s rum coffee. Paul Stephen, ExpressNews.com, "Updated Northside ISD cookbook: Nearly 900+ recipes of puro San Antonio cooking," 24 Dec. 2019 If your little one goes loco for locomotives, then this annual event is as good as Christmas. Web Behrens, chicagotribune.com, "15 things to do with the kids July 8-14," 7 July 2019 Onboard the Tejas Express, the IRCTC will have its own staff, such as ticket checkers, and service crew, though the loco pilots and guards will belong to Indian Railways. Manavi Kapur, Quartz India, "India flags off its first privately-run train with airline-like facilities," 4 Oct. 2019 After extensive research, Thomas came up with about a dozen dishes — including an elaborate loco moco burger preparation that didn’t make the cut — that was eventually trimmed to seven items. Pam Kragen, San Diego Union-Tribune, "Gourmet dog diner opens on Carlsbad restaurant’s patio," 5 Sep. 2019 The menu was big — kimchi fried rice, loco moco, burgers, burritos, French toast, eggs, not to mention the different meat options — so waste was an issue. Janelle Bitker, SFChronicle.com, "Huli Huli Hawaiian Grill to become Sunday Gather. The transition hasn’t exactly been smooth," 3 Sep. 2019 Brunch items range from loco moco to eggs Benedict. Tan Vinh, The Seattle Times, "Loosen your belt: 46 more restaurant and ice cream openings in Seattle and on the Eastside to try," 25 June 2018 Moscow The first week of the 2018 World Cup has produced its share of shocks and upsets, but amid all the nutty results, only one can be regarded as completamente loco. Jonathan Clegg, WSJ, "Mexico’s World Cup Run Is Built on Benchwarmers," 22 June 2018 Recent Examples on the Web: Adjective Real investors survey the landscape and look for signs of a market gone loco. Andy Kessler, WSJ, "For Whom the Bell Tolls, Sell," 2 July 2017 As one of my colleagues said, this was straight loco. Ryu Spaeth, New Republic, "Anthony Scaramucci: Harder, Better, Faster, Crazier.," 28 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'loco.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of loco

Adverb or adjective

1786, in the meaning defined above


1844, in the meaning defined at sense 1


1884, in the meaning defined at sense 1


1852, in the meaning defined above

History and Etymology for loco

Adverb or adjective

Italian dialect, there, from Latin in loco in the place


Mexican Spanish, from Spanish, crazy



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Cite this Entry

“Loco.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/loco. Accessed 8 Jul. 2020.

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More Definitions for loco


lo·​co | \ ˈlō-(ˌ)kō How to pronounce loco (audio) \
plural locos or locoes

Medical Definition of loco

 (Entry 1 of 2)

Medical Definition of loco (Entry 2 of 2)

: to poison with locoweed

More from Merriam-Webster on loco

Thesaurus: All synonyms and antonyms for loco

Spanish Central: Translation of loco

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