vacillate
VAS-uh-layt
/ˈvæsɪleɪt/
To waver between different opinions or actions; to be indecisive.
Suggests a physical or mental swaying back and forth, often due to weakness of will or an inability to make up one's mind under pressure.
The story behind the word. The Latin verb vacillare originally described a physical staggering or swaying, like a person who is tipsy or a poorly balanced cart on a bumpy road. By the 1600s, English writers began using it metaphorically to describe a mind that sways unsteadily between two choices.
Word relationships
- waver: 'Waver' is more common and can apply to physical objects (like a flickering flame), whereas 'vacillate' is more formal and usually refers to mental indecision.
- oscillate: 'Oscillate' usually refers to a regular, physical swinging motion (like a pendulum), while 'vacillate' refers to erratic mental hesitation.
- decide: 'Decide' means to make a firm choice, ending all hesitation, whereas 'vacillate' is the state of ongoing hesitation.
Commonly confused with
- equivocate: 'Vacillate' is an internal state of indecision (not knowing what to choose), whereas 'equivocate' is an external act of speaking deceptively or ambiguously to avoid committing to a stance.
Word family
- vacillation (noun): The state of wavering in mind or opinion; indecision.
- vacillating (adjective): Characterized by wavering or indecision.
Collocations
- vacillate between options
- tendency to vacillate
- vacillate wildly
Idioms & expressions
- blow hot and cold
- sit on the fence
Example sentences
- "If you vacillate too long between the two marketing strategies, our competitors will capture the market share." An executive unable to choose a strategy.
- "I vacillate between the two opinions." A famous scientific letter expressing hesitation.
Memory hook
Think of a 'vacuums' hose swinging wildly back and forth on the floor. It can't stay still, just like a vacillating mind. Vacillate like a pendulum.
When not to use
Do not use when someone is carefully and systematically weighing options in a balanced, healthy way; use 'deliberate' instead.
Fun facts
- In physics, the term 'vacuum fluctuation' sounds similar but is unrelated; however, both involve a state of constant, unpredictable shifting!
Related words
Explore more words
sway, equivocal, tremulous, prevarication, prevaricate, Oscillation
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