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

The researchers found that the hybrid wave periodically oscillated between sound and spin states. —Aamir Khollam, Interesting Engineering, 29 Nov. 2025

Certain kinds of atomic nuclei—including those of the hydrogen atoms in a water molecule—can be made to oscillate in a magnetic field, and these oscillations can be detected with coils of wire. —David Schneider, IEEE Spectrum, 25 Nov. 2025

More details of the government’s spending and tax plans are due to be unveiled Wednesday, in which Chancellor Rachel Reeves, the UK’s finance minister, is expected to address the two-child benefit cap, a policy the government has oscillated between keeping and scrapping for the past year. —Issy Ronald, CNN Money, 24 Nov. 2025

Kenny thinks of it in the same way as Star Wars and the oscillating reactions to the releases that came out after the original trilogy, including the prequels. —Nick Romano, Entertainment Weekly, 24 Nov. 2025

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

Rhymes for oscillate

• abdicate
• abrogate
• acetate
• activate
• actuate
• adsorbate
• aggravate
• agitate
• alginate
• alienate
• allocate
• amputate

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