vacillate

/ˈvæsɪleɪt/ · VAS-ih-laytverb

Alternate indecisively between different opinions, choices, or courses of action.

Use vacillate to express this relationship precisely: alternate indecisively between different opinions, choices, or courses of action.

What vacillate Really Means

The word becomes easier to use when its closely related senses are separated and compared.

1

Core action

Alternate indecisively between different opinions, choices, or courses of action.

Example

The committee vacillated between expansion and repair.

2

Common construction

Use this expression in its normal grammatical frame so the relationship between the surrounding ideas remains explicit.

Example

He continued to vacillate on whether to publish the results.

3

Reasoning effect

It tells the reader how to interpret the timing, scope, evidence, contrast, condition, or consequence in the statement.

Example

Markets vacillated between optimism and concern.

Use vacillate Naturally

Notice how the surrounding noun or clause reveals the exact shade of meaning.

The committee vacillated between expansion and repair.

He continued to vacillate on whether to publish the results.

Markets vacillated between optimism and concern.

Precision Matters

Vacillate overlaps with several common words, but each carries a different emphasis.

vacillate

Means alternate indecisively between different opinions, choices, or courses of action.

vs.
ambivalence

Means simultaneous conflicting feelings about something.

vacillate

Means alternate indecisively between different opinions, choices, or courses of action.

vs.
capricious

Means given to sudden, unpredictable changes in mood, behaviour, or decision.

vacillate

Means alternate indecisively between different opinions, choices, or courses of action.

vs.
adamant

Means firmly refusing to change a decision, belief, or position.

vacillate

Means alternate indecisively between different opinions, choices, or courses of action.

vs.
tentative

Means provisional, hesitant, or not yet certain, fixed, or fully developed.

Test vacillate in Context

The council moves indecisively back and forth between two options.

1

Unable to choose either proposal, the council continued to ___ between them.

Prepared byFirst Academy
Editorial responsibilityFirst Academy Academic Team
Updated3 August 2026
Selection and reviewRead our methodology