I. ˈyȯ noun
Etymology: origin unknown
Date: 1546
1. : the action of yawing ; especially : a side to side movement
2. : the extent of the movement in yawing
II. intransitive verb
Date: 1586
1.
a. of a ship : to deviate erratically from a course (as when struck by a heavy sea) ; especially : to move from side to side
b. of an airplane, spacecraft, or projectile : to turn by angular motion about the vertical axis
2. : alternate
restlessly yaw ing between apparent extremes — Martin Kasindorf