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
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” ( see 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
List 1
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To Kill a Mockingbird
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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.
Hader’s elastic voice rides in a higher range than usual, but he also mixes it up, expressing the many multifaceted aspects of the Cat’s erratic personality.
From Los Angeles Times ● Nov. 6, 2026
It has become more erratic and unreliable since the pandemic, at least on first read.
From MarketWatch ● Nov. 5, 2026
Ostapenko often took the racquet out of Kartal's hands with her explosive - and often erratic - brand of first-strike tennis, but Chwalinska was a different proposition.
From BBC ● Oct. 18, 2026
A recent change of finance minister ruffled some feathers, but the selection of Suahasil Nazara—an experienced technocrat with a solid record—has soothed some worries about erratic policymaking, analyst say.
From The Wall Street Journal ● Oct. 15, 2026
Calpurnia was sitting in a haughty dignity that appeared on state occasions, and with it appeared erratic grammar.
From "Go Set a Watchman: A Novel" by Harper Lee
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Get a wordDefinitions 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.
