unicycle

American  

[yoo-nuh-sahy-kuhl] / ˈyu nəˌsaɪ kəl /

noun

1. a vehicle with one wheel, especially a pedal-driven device kept upright and steered by body balance, commonly used by acrobats and other performers.

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verb (used without object)

unicycled, unicycling

1. to ride a unicycle.

unicycle British  

/ ˈjuːnɪˌsaɪkəl /

noun

1. Also called: monocycle.  a one-wheeled vehicle driven by pedals, esp one used in a circus, etc

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Other Word Forms

• unicyclist noun

Etymology

Origin of unicycle

An Americanism dating back to 1865–70; uni- + cycle

Example Sentences

A man on a unicycle brandished a sign, inspired by J.R.R.

From The Wall Street Journal • Feb. 8, 2026

Riding on her custom-made unicycle at least 7 feet off the floor, Red Panda appeared to lose her balance early in her routine, then fell forward off her seat.

From Los Angeles Times • Jul. 2, 2025

Other days you might see a dog wearing an LED collar or a kid riding an electric unicycle to school and feel momentarily convinced that, yes, the future is actually here.

From Washington Post • Sep. 27, 2022

Rick Madeira, of Fall River, has taken to riding his electric unicycle to work, saving on gas and cutting his commute time in the process.

From Seattle Times • Mar. 24, 2022

And so we watched it all: the eighteen-year-old boy with a fake mustache who did a magic show and juggled flaming hoops while riding a unicycle.

From "The Joy Luck Club" by Amy Tan