• To bend or incline the upper part, with a quick motion; as, nodding plumes. • To incline the head with a quick motion; to make a slight bow; to make a motion of assent, of salutation, or of drowsiness, with the head; as, to nod at one. • To be drowsy or dull; to be careless. • To incline or bend, as the head or top; to make a motion of assent, of salutation, or of drowsiness with; as, to nod the head. • To signify by a nod; as, to nod approbation. • To cause to bend. • A dropping or bending forward of the upper oart or top of anything. • A quick or slight downward or forward motion of the head, in assent, in familiar salutation, in drowsiness, or in giving a signal, or a command.