loco
1 of 4adverb or adjective
lo·co
ˈlō-(ˌ)kō 
: in the register as written
—used as a direction in music
plural locos or locoes
: any of several leguminous plants (genera Astragalus and Oxytropis) of western North America that contain a toxin that causes locoism especially in livestock when ingested in large quantities : locoweed
locoed; locoing; locos
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.
Recent Examples on the Web
Jen Murphy, Outside Online, 29 Dec. 2022
Irene Adeline Milanez, Sacbee.com, 22 June 2025
Tren de Aragua, the Venezuelan prison gang whose name means Train of Aragua, is putting the loco in locomotive with a New York City robbery spree that sees its young members repeatedly stay out of jail.
—Michael Ruiz, Fox News, 15 Oct. 2024
Andy Kessler, WSJ, 2 July 2017
As one of my colleagues said, this was straight loco.
—Ryu Spaeth, New Republic, 28 July 2017
See All Example Sentences for loco
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Adverb or adjective
Breakfast hits include mahi eggs Benedict and loco moco, a hearty Hawaiian staple of eggs, a beef patty, and steamed rice smothered in a rich gravy.
—Jen Murphy, Outside Online, 29 Dec. 2022
Noun
Though Sunny Side’s addition of vegetables and cheddar cheese sets itself apart from a traditional loco moco, it’s named after Hilo, Hawaii, where the dish originates from.
—Irene Adeline Milanez, Sacbee.com, 22 June 2025
Tren de Aragua, the Venezuelan prison gang whose name means Train of Aragua, is putting the loco in locomotive with a New York City robbery spree that sees its young members repeatedly stay out of jail.
—Michael Ruiz, Fox News, 15 Oct. 2024
Adjective
Real investors survey the landscape and look for signs of a market gone loco.
—Andy Kessler, WSJ, 2 July 2017
As one of my colleagues said, this was straight loco.
—Ryu Spaeth, New Republic, 28 July 2017
See All Example Sentences for loco
Cite this Entry
“Loco.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/loco. Accessed 8 Jul. 2025.
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