erratic meaning: definition, etymology and quotations

erratic

adj

UK /ɪˈɹætɪk/ · AU, CA, US /ɪˈɹætɪk/

Etymology From Middle English erratik, erratyk, from Latin errāticus; compare Old French erratique.

Unsteady, random; prone to unexpected changes; not consistent.

Henry has been getting erratic scores on his tests: 40% last week, but 98% this week.
The V-2's directional system was notoriously erratic. In May 1947, a V-2 launched from White Sands Proving Ground headed south instead of north, missing downtown Juarez, Mexico, by 3 miles.2010, Mary Roach, “You Go First: The Alarming Prospect of Life Without Gravity”, in Packing for Mars: The Curious Science of Life in the Void, W. W. Norton & Company, →ISBN, page 90:

Deviating from normal opinions or actions; eccentric; odd.

Antonyms: consistent
Derived terms: erratical, erratically, erraticism, erraticity, erraticness, glacial erratic, inerratic, knight-erratic, nonerratic, unerratic

noun

Etymology From Middle English erratik, erratyk, from Latin errāticus; compare Old French erratique.

Geography, Geology, Natural sciences A rock moved from one location to another, usually by a glacier.

The term for a displaced boulder is an erratic, but in the nineteenth century the expression seemed to apply more often to the theories than to the rocks.2003, Bill Bryson, A Short History of Nearly Everything, BCA, page 372:
During the last ice-age, massive stones were carried for miles by the scouring glaciers, only to be left, like passengers at the end of the line, when the glaciers retreated. Stranded in their new surroundings with rocks with which they share no common geology, their out-of-place-ness is evoked by their name: “erratics”.2015 May 4, Dominick Tyler, “10 UK landscape features that you’ve probably never heard of”, in The Guardian:

Anything that has erratic characteristics.

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.