Nod means 'to quickly and briefly move the head up and down to say hello or express approval.' It also means 'to let the head fall forward suddenly and involuntarily because you are extremely tired.' As a noun, a nod is the up and down movement made with the head.
The kids were asleep when I came in, and she just looked at me and nodded.
Tess finished her presentation and her bossnoddedin approval.
I was so tired when I got on the bus that my head was noddingall the way home and I nearly missed my stop!
With just a slight nod, Mario let his kids know they could go to the dance.
Words often used with nod
nod off: to fall asleep, especially for a short period of time. We often use this when we fall asleep and don't want to. Example: "I tried to stay awake until the end of the film, but I just kept nodding off."
give/get the nod (or get/give the nod of approval): to give or receive approval for something. Example: "We can't start the project yet; we're waiting for the boss to give us the nod."
The opposite of nod ('move your head to express approval') is shake your head. Example: "Nod if you agree with me and shake your head if you disagree."
Did you know?
The land of Nod is the biblical place mentioned in the book of Genesis as east of Eden, where God exiled Cain after he killed his brother, Abel. These days, the land of Nod is a popular metaphor for sleep: "Veronica fell asleep on the train. When she woke up, she was surprised at how much the countryside had changed while she was in the land of Nod."
nodder (noun), nodding (adjective)
Nod dates back to the second half of the 14th century, where it first appeared as the Middle English word nodde. Its precise origin is uncertain.