Loco

How to spell loco

4 letters · 2 syllables

How to pronounce loco

Say the part in capitals loudest.

What does loco mean?

1. adjectiveInformal term meaning mad, crazy, or wildly irrational.

Loco in a sentence

• The constant overtime was driving the whole team loco.

• Spending that much on a sofa seemed completely loco to her.

Where does loco come from?

Language of origin: Spanish

In its 'crazy' sense this word was borrowed directly from Spanish loco, meaning 'mad' or 'insane', a word whose own earlier roots are uncertain and may trace back to an Arabic term for a fool or an idiot. It rode into American English during the nineteenth century along the cattle trails and ranches of the Southwest, where Spanish-speaking and English-speaking communities mixed freely. American ranchers also met it in the name of a poisonous plant, the loco weed, which sent grazing horses and cattle into staggering, deranged behaviour, reinforcing the sense of madness. The completely separate railway sense, meaning a locomotive, is simply a clipped shortening of that longer word, popular among British enthusiasts and rail workers. Because the same four letters carry two unrelated histories, the slang sense from Spanish and the engine sense from Latin via locomotive, the spelling stays identical even though the stories do not meet.

How the word is built

• loco (Spanish: mad, insane); the railway sense is a clipping of locomotive