oscillation

noun

os·​cil·​la·​tion ˌä-sə-ˈlā-shən 

1

: the action or state of oscillating

… stays can be effectively used to prevent oscillations in new bridges …

—D. B. Steinman

2

: variation, fluctuation

… famines due to excessive storminess and violent oscillations of rain and drought, heat and cold.

—Ellsworth Huntington

3

: a flow of electricity changing periodically from a maximum to a minimum

especially : a flow periodically changing direction

4

: a single swing (as of an oscillating body) from one extreme limit to the other

Each oscillation of the pendulum represents one second.

oscillational

ˌä-sə-ˈlā-sh(ə-)nəl 

adjective

Synonyms of oscillation

• fluctuation
• change

Examples of oscillation in a Sentence

the continued oscillation of the fan

There has been oscillation between optimism and pessimism among voters.

Recent Examples on the Web

Two airflow outlets on either side of the loop can be configured for 0, 45, or 90 degrees of oscillation action. —John R. Delaney, PC Magazine, 28 Apr. 2026

One of the key targets of the NGRST surveys is what are called baryon acoustic oscillations. —John Timmer, ArsTechnica, 23 Apr. 2026

That is an oscillation of the Moon, causing parts near the edge of the disc that are often not visible from the Earth to sometimes come into view. —Ray Petelin, CBS News, 18 Apr. 2026

There are some adjustments that stand out — the Nationals are crushing fastballs and swinging less with two strikes — but overall, this is an offense of oscillation. —Spencer Nusbaum, New York Times, 13 Apr. 2026

Word History

First Known Use

1658, in the meaning defined at sense 1

Rhymes for oscillation

• abdication
• aberration
• abjuration
• abnegation
• abrogation
• acceptation
• acclamation
• acclimation
• accusation
• activation
• actuation
• acylation

Kids Definition

oscillation

noun

os·​cil·​la·​tion ˌäs-ə-ˈlā-shən 

1

: the action or state of oscillating : vibration

2

: variation sense 1, fluctuation

3

: a single swing (as of an oscillating body) from one extreme limit to the other

Medical Definition

oscillation

noun

os·​cil·​la·​tion ˌäs-ə-ˈlā-shən 

1

: the action or state of oscillating

2

: a flow of electricity changing periodically from a maximum to a minimum

especially : a flow periodically changing direction