Hornbeam (Carpinus) forms a genus of relatively small hardwood trees, placed in the hazel family Corylaceae, though some botanists include this family within the birch family Betulaceae.

The European hornbeam (Carpinus betulus) is a small- to medium-sized tree of Europe. The common name now also applies to other species of Carpinus from the north temperate regions. The greatest number of species occurs in China and east Asia.

The North American species, American hornbeam (Carpinus caroliniana), is also known as blue-beech, ironwood, and musclewood. The various common names come from the resemblance of the bark to that of the American beech Fagus grandifolia, the hardness of the wood and the muscular appearance of the trunk.

The wood is not used much due to the small size of the tree, but its hardness has lent it to carving boards, toolmaking, coach wheels and other crafts requiring hardness over quantity.