erratic
Americanadjective
-
deviating from the usual or proper course in conduct or opinion; eccentric.
erratic behavior.
- Synonyms:
- capricious, unstable, unpredictable
- Antonyms:
- stable, regular, consistent
-
inconsistent, irregular, or unpredictable.
Many factors affect purchasing power, such as inflation and erratic swings in the stock market.
-
having no certain or definite course or pattern; wandering; not fixed.
erratic winds.
-
Geology. noting or pertaining to a boulder or the like carried by glacial ice and deposited some distance from its place of origin.
-
(of a lichen) having no attachment to the surface on which it grows.
noun
-
an erratic or eccentric person.
-
Geology. an erratic boulder or the like.
adjective
-
irregular in performance, behaviour, or attitude; inconsistent and unpredictable
-
having no fixed or regular course; wandering
noun
-
a piece of rock that differs in composition, shape, etc, from the rock surrounding it, having been transported from its place of origin, esp by glacial action
-
an erratic person or thing
Other Word Forms
- erratically adverb
- erraticism noun
- nonerratic adjective
- unerratic adjective
Etymology
Origin of erratic
First recorded in 1325–75; Middle English, from Latin errāticus, equivalent to errāt(us) (past participle of errāre “to make a mistake, err” ( err ) + -icus -ic
Explanation
The adjective erratic describes things that are unpredictable, unusual, and that deviate from the norm. An erratic quarterback might completely confuse his receivers waiting for a pass. Like its linguistic relative, error, the adjective erratic means "deviating from the norm," or "wrong." It also implies behavior or qualities that are unpredictable or odd. The word comes from the Latin verb errare, or "to wander" off course. In the field of geology, a rock that is erratic is unlike others in its environment because it has been transported by glacial activity. Likewise, someone driving a car that veers out of its lane is said to be driving erratically.
Vocabulary lists containing erratic
To Kill a Mockingbird
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List 1
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"To Kill a Mockingbird" by Harper Lee, Chapters 1–6
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
It cites a record of "incredibly alarming and erratic banking behavior" in her own Bank of America accounts, which were used by Epstein's team.
From BBC • Mar. 16, 2026
Meanwhile, the 2025 novel “Unfit” by Ariana Harwicz, about a mother losing her children in a custody battle, uses erratic crayon scribbles on its cover.
From Los Angeles Times • Mar. 16, 2026
Merz's first official visit to China comes as Berlin and Beijing seek to build on decades-old economic ties to weather global uncertainty sparked by US President Donald Trump's tariff blitz and erratic foreign policies.
From Barron's • Feb. 26, 2026
Funding has often been erratic and delayed, but the deeper problem is that our current weapons were never designed for mass production.
From The Wall Street Journal • Feb. 24, 2026
The perceptions come without warnings or explanations, erratic as lightning.
From "Dreaming in Cuban" by Cristina García
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
