oscillate

verb

os·​cil·​late ˈä-sə-ˌlāt 

oscillated; oscillating

intransitive verb

1

a

: to swing backward and forward like a pendulum

The fan was oscillating.

b

: to move or travel back and forth between two points

he oscillates regularly between his comfortable home … and his downtown office-laboratory

—Gladwin Hill

2

: to vary between opposing beliefs, feelings, or theories

The mood of the voters has oscillated between optimism and pessimism.

3

: to vary above and below a mean value

Bank rate oscillates between 2 and 6 percent.

oscillatory

ˈä-sə-lə-ˌtȯr-ē 

adjective

Choose the Right Synonym for oscillate

swing, sway, oscillate, vibrate, fluctuate, waver, undulate mean to move from one direction to its opposite.

swing implies a movement of something attached at one end or one side.

the door suddenly swung open

sway implies a slow swinging or teetering movement.

trees swaying in the breeze

oscillate stresses a usually regular alternation of direction.

an oscillating fan

vibrate suggests the rapid oscillation of an elastic body under stress or impact.

the vibrating strings of a piano

fluctuate suggests constant irregular changes of level, intensity, or value.

fluctuating interest rates

waver stresses irregular motion suggestive of reeling or tottering.

the exhausted runner wavered before collapsing

undulate suggests a gentle wavelike motion.

an undulating sea of grass

Examples of oscillate in a Sentence

Recent Examples on the Web

By turns, the two women appear loving, then competitive — combative even — oscillating between precise unity and independence, staring at each other often but not touching until halfway through. —Lauren Warnecke, Chicago Tribune, 20 Jan. 2025

Palmer has been oscillating between spurts of lively color and sultry, leather-heavy black. —Hannah Jackson, Vogue, 18 Jan. 2025

Without that, the pendulum, once excited, would oscillate for too long. —IEEE Spectrum, 2 Jan. 2025

Historical data reveals that water levels on the Great Lakes, including Lake Superior, have oscillated dramatically in recent decades. —David Faris, Newsweek, 28 Dec. 2024

Word History

Etymology

Latin oscillatus, past participle of oscillare to swing, from oscillum swing

First Known Use

1726, in the meaning defined at sense 1a

Kids Definition

oscillate

verb

os·​cil·​late ˈäs-ə-ˌlāt 

oscillated; oscillating

1

a

: to swing backward and forward like a pendulum

b

: to move or travel back and forth between two points

2

: to have trouble deciding between opposing beliefs, feelings, or ideas

oscillatory

ˈäs-ə-lə-ˌtōr-ē 

-ˌtȯr-

adjective

Medical Definition

oscillate

intransitive verb

os·​cil·​late ˈäs-ə-ˌlāt 

oscillated; oscillating

1

: to swing backward and forward like a pendulum

2

: to move or travel back and forth between two points

oscillatory

ˈäs-ə-lə-ˌtōr-ē, -ˌtȯr- 

adjective