The hornbeam (Carpinus betulus), is a small to medium sized tree of Europe, placed in the birch family (Betulaceae). The common name is now applied also to other species of Carpinus from the north temperate regions. The greatest number of species is found in China and east Asia.

The North American species Carpinus carolinianus 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 toolmaking and other crafts requiring hardness over quantity.