1. The seed or fruit of the oak; an oval nut which grows in a rough permanent cup.
The first settlers of Boston were reduced to the necessity of feeding on clams, muscles, ground nuts, and acorns.
2. In marine language, a small ornamental piece of wood, of a conical shape, fixed on the point of the spindle above the vane, on the mast head, to keep the vane from being blown off.
3. In natural history, the Lepas, a genus of shells of several species found on the British coast. The shell is multivalvular, unequal, and fixed by a stem; the valves are parallel and perpendicular, but they do not open, so that the animal performs its functions by an aperture on the top. These shells are always fixed to some solid body.