loco

[ loh-koh ]

/ ˈloʊ koʊ /

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See synonyms for loco on Thesaurus.com

noun, plural lo·cos.

locoweed.

Slang. an insane person; maniac.

Veterinary Pathology. locoism.

verb (used with object), lo·coed, lo·co·ing.

to poison with locoweed.

Slang. to cause to be insane or crazy.

adjective

Slang. out of one's mind; insane; crazy.

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Origin of loco

1835–45, Americanism;<Spanish: insane

Words nearby loco

lockup, lock washer, Lockwood, Lockwood home, Lockyer, loco, loco citato, loco disease, Locofoco, Locofocoism, locoism

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use loco in a sentence

Reddit users worldwide went loco for the opportunity to ask the president of Taco Bell anything.
The Best of Taco Bell’s Reddit AMA|The Daily Beast|March 28, 2014|DAILY BEAST
Cameron is in essence assuming the role of in loco parentis in relation to almost every household in Britain.
Britain’s Idiotic “Opt-In” Porn Ban|Brendan O’Neill|November 23, 2013|DAILY BEAST
“Children of the Corn” borrows a lot of pulp staples: a found body; a rural hamlet; religion gone loco; evil kids.
Great New Reads|The Daily Beast|October 31, 2010|DAILY BEAST
Seqvitvr iam ex initio propositis tertium, nimirum vt exponatur, quonam tand loco rem Christianam his in locis offenderimus.
The Jesuit Relations and Allied Documents, Vol. II: Acadia, 1612-1614|Various

I perceive the deadly loco's odor there, and say it poison is; it drives them mad for evermore.
A Fortune Hunter; Or, The Old Stone Corral|John Dunloe Carteret
Mastrius (loco jam citato) tenet inseminationem esse necessariam.
Essays In Pastoral Medicine|Austin Malley
There is a very real sense in which the crowd stands to his emotional life in loco parentis.
The Behavior of Crowds|Everett Dean Martin
In another connection I have referred to the fact that the crowd stands to the member in loco parentis.
The Behavior of Crowds|Everett Dean Martin

British Dictionary definitions for loco (1 of 3)

loco¹

/ (ˈləʊkəʊ) /

noun

informal short for locomotive

British Dictionary definitions for loco (2 of 3)

loco²

/ (ˈləʊkəʊ) /

adjective

slang, mainly US insane

(of an animal) affected with loco disease

noun plural -cos

short for locoweed

verb (tr)

to poison with locoweed

US slang to make insane

Word Origin for loco

C19: via Mexican Spanish from Spanish: crazy

British Dictionary definitions for loco (3 of 3)

loco³

/ (ˈləʊkəʊ) /

adjective

denoting a price for goods, esp goods to be exported, that are in a place specified or known, the buyer being responsible for all transport charges from that placeloco Bristol; a loco price

Word Origin for loco

C20: from Latin locō from a place

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

loco

Origin of loco

Words nearby loco

Words related to loco

How to use loco in a sentence

British Dictionary definitions for loco (1 of 3)

British Dictionary definitions for loco (2 of 3)

Word Origin for loco

British Dictionary definitions for loco (3 of 3)

Word Origin for loco