葉 (ha) means “leaf” | MotiTan Japanese Dictionary

More examples

秋になると、木の葉が赤くなります。aki ni na ru to ki no ha ga aka ku na ri ma su

In autumn, the leaves on the trees turn red.

Refers to the plant part that grows from a stem or branch and carries out photosynthesis.

葉っぱhappa: A casual word for the plant part that grows from a stem or branch and uses sunlight to make food.

植物の茎や枝から生じ、光合成などを行う器官。shoku butsu no kuki ya eda ka ra shō ji hikari gō sei na do o okona u ki kan

The word 葉 (ha, "leaf") is a native Japanese noun attested in Old Japanese as pa, and no secure earlier derivation is known.

In Japanese, 葉 (ha, "leaf") does not mark singular or plural, so context can make it mean one leaf or foliage.