Any tree or shrub of the genus Quercus. The oaks have alternate leaves, often variously lobed, and staminate flowers in catkins. The fruit is a smooth nut, called an acorn, which is more or less inclosed in a scaly involucre called the cup or cupule. There are now recognized about three hundred species, of which nearly fifty occur in the United States, the rest in Europe, Asia, and the other parts of North America, a very few barely reaching the northern parts of South America and Africa. Many of the oaks form forest trees of grand proportions and live many centuries. The wood is usually hard and tough, and provided with conspicuous medullary rays, forming the silver grain. (Bot.)
The strong wood or timber of the oak.
Phrases & Compounds
Green oak
oak wood colored green by the growth of the mycelium of certain fungi.
Oak apple
a large, smooth, round gall produced on the leaves of the American red oak by a gallfly (Cynips confluens). It is green and pulpy when young.
Oak beauty
a British geometrid moth (Biston prodromaria) whose larva feeds on the oak.
a kind of gall produced on the oak by the insect Diplolepis lenticularis.
Oak wart
a wartlike gall on the twigs of an oak.
The Oaks
one of the three great annual English horse races (the Derby and St. Leger being the others). It was instituted in 1779 by the Earl of Derby, and so called from his estate.
To sport one's oak
to be “not at home to visitors,” signified by closing the outer (oaken) door of one's rooms.