A deciduous tree of the genus Quercus; has acorns and lobed leaves WordNet 3.0 & Open English WordNet

An oak is a hardwood tree or shrub in the genus Quercus of the beech family. Wikipedia

Tree or shrub in the genus Quercus in the plant family Fagaceae. Wikipedia Disambiguation

A tree or shrub in the genus Quercus Wikipedia Disambiguation

Tree or shrub in the genus Quercus Wikidata

Any tree of the genus Quercus in the order Fagales, characterized by simple, usually lobed leaves, scaly winter buds, a star-shaped pith, and its fruit, the acorn, which is a nut; the wood is tough, hard, and durable, generally having a distinct pattern. OmegaWiki

Wood of the oak tree. OmegaWiki

A deciduous tree with distinctive deeply lobed leaves, acorns, and notably strong wood, typically of England and northeastern North America, included in genus Quercus. Wiktionary

Wood. Wiktionary (translation)

A tree of the genus Quercus, bearing acorns and having lobed leaves. Wiktionary