1.
unicycle
A single-wheeled pedal vehicle ridden for recreation or performance. A common activity in Japanese elementary schools.
2.
wheelbarrow
A single-wheeled cart pushed by hand, used for carrying loads at construction sites, gardens, and farms.
Usage
一輪車 has two distinct meanings depending on context. In everyday conversation, especially among children and families, it usually means unicycle. In construction or gardening contexts, it means wheelbarrow.
Cultural note
Unicycle riding is a common activity at Japanese elementary schools. Many schools have unicycles available for students to use during recess, and some hold unicycle competitions.