oak: Meaning and Definition of

oak

1. any tree or shrub belonging to the genus Quercus, of the beech family, bearing the acorn as fruit.
2. the hard, durable wood of such a tree, used in making furniture and in construction.
3. the leaves of this tree, esp. as worn in a chaplet.
4. anything made of the wood of this tree, as an item of furniture, a door, etc.
5. (of a university student) to indicate that one is not at home to visitors by closing the outer door of one's lodgings.