(nod) noun
A forward and downward motion of the head, more or less quick or jerky; also, a similar motion of the top of anything, as a tree. [<v.]
—v. nod·ded, nod·ding v.i.
1. To make a brief forward and downward movement of the head, as in agreement, invitation, etc.
2. To let the head fall forward briefly and involuntarily, as when drowsy; be sleepy.
3. To be inattentive or careless; make an error.
4. To incline the top or upper part as if nodding: said of trees, flowers, etc.
—v.t.
5. To bend (the head) forward and downward briefly.
6. To express or signify by nodding: to nod approval.
7. To affect in a specified manner by nodding: He nodded me from the room. [Cf. G notteln shake]
—nod′der noun

(nod), Land of
1. The land east of Eden in which Cain settled after killing Abel. Gen. iv 16.
2. Sleep.