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

Tyran Stokes, hailed as the top prospect in the high school class of 2026, has bounced up and down the West Coast, attending three different high schools in four years, while fans on Reddit scrutinize his performance and national media agonize over his oscillating college decision. —Leah Asmelash, CNN Money, 8 Apr. 2026

How quickly neutrinos oscillate depends on the difference between the neutrino masses. —Quanta Magazine, 8 Apr. 2026

The fan also oscillates at a 70-degree angle and can cover a large portion of the room, distributing cool air throughout. —George Yang, PC Magazine, 6 Apr. 2026

Service, on my visits, was a bit spacey, but it’s been tightening up; the tone of the place seems to be in progress, too, oscillating between that of a neighborhood joint, an amorous date-night nook, and a sceney hot spot. —Helen Rosner, New Yorker, 5 Apr. 2026

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