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adjective er·rat·ic \i-ˈra-tik\

Simple Definition of erratic

  • : acting, moving, or changing in ways that are not expected or usual : not consistent or regular

Source: Merriam-Webster's Learner's Dictionary

Full Definition of erratic

  1. 1 a :  having no fixed course :  wandering <an erratic comet> b archaic :  nomadic

  2. 2 :  transported from an original resting place especially by a glacier <an erratic boulder>

  3. 3 a :  characterized by lack of consistency, regularity, or uniformity <erratic dieting> <keeps erratic hours> b :  deviating from what is ordinary or standard :  eccentric <an erratic genius>

erratical play \-ti-kəl\ adjective
erratically play \-ti-k(ə-)lē\ adverb
erraticism play \-ˈa-tə-ˌsi-zəm\ noun

Examples of erratic in a sentence

  1. My sinker has been my most erratic pitch. And when your foundation pitch is lacking, you have to go to other pitches. My sinker has been in and out, but mostly out. —Orel Hershiser, in New York Times, 9 May 1999

  2. In winning his two-month match in Yugoslavia against Boris Spassky, 10 games to five, Bobby Fischer was erratic, which was hardly surprising considering his two-decade layoff, but there were times when he played more brilliantly than anybody could have expected. —Sports Illustrated, 16 Nov. 1992

  3. Over the centuries, in erratic ways, men have constructed a world in which they are relatively free of many kinds of threatening or harmful stimuli … —B. F. Skinner, Beyond Freedom and Dignity, (1971) 1972

  4. <so far your effort to land a summer job has been very erratic>

  5. <because of your erratic attendance at practice, you're in danger of being cut from the team>

Origin of erratic

Middle English, from Latin erraticus, from erratus, past participle of errare (see err)

First Known Use: 14th century

Synonym Discussion of erratic

strange, singular, unique, peculiar, eccentric, erratic, odd, quaint, outlandish mean departing from what is ordinary, usual, or to be expected. strange stresses unfamiliarity and may apply to the foreign, the unnatural, the unaccountable <a journey filled with strange sights>. singular suggests individuality or puzzling strangeness <a singular feeling of impending disaster>. unique implies singularity and the fact of being without a known parallel <a career unique in the annals of science>. peculiar implies a marked distinctiveness <the peculiar status of America's first lady>. eccentric suggests a wide divergence from the usual or normal especially in behavior <the eccentric eating habits of preschoolers>. erratic stresses a capricious and unpredictable wandering or deviating <a friend's suddenly erratic behavior>. odd applies to a departure from the regular or expected <an odd sense of humor>. quaint suggests an old-fashioned but pleasant oddness <a quaint fishing village>. outlandish applies to what is uncouth, bizarre, or barbaric <outlandish fashions of the time>.



noun er·rat·ic \i-ˈra-tik\

Definition of erratic

  1. :  one that is erratic (see 1erratic); especially :  a boulder or block of rock transported from its original resting place especially by a glacier

Origin of erratic

(see 1erratic)

First Known Use: circa 1623

ERRATIC Defined for Kids


adjective er·rat·ic \i-ˈra-tik\

Definition of erratic for Students

  1. :  not consistent or regular <erratic behavior> <erratic movements>

Medical Dictionary


adjective er·rat·ic \ir-ˈat-ik\

Medical Definition of erratic

  1. 1:  characterized by lack of consistency, regularity, or uniformity <an erratic pulse>

  2. 2:  deviating from what is ordinary or standard

Seen and Heard

What made you want to look up erratic? Please tell us where you read or heard it (including the quote, if possible).


a timid, meek, or unassertive person

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