duck
To quickly lower (the head or body), often in order to prevent it from being struck by something.
Other meanings
To lower (something) into water; to thrust or plunge under liquid and suddenly withdraw.
To go under the surface of water and immediately reappear; to plunge one's head into water or other liquid.
Word history
From Middle English "ducken".
Where this comes from
This definition is adapted from “duck” on Wiktionary, by its contributors, published under CC BY-SA 4.0. This page is published under the same licence.