Erratic Definition

ĭ-rătĭk

adjective

Having no fixed course or purpose; irregular; random; wandering.

Webster's New World

Lacking consistency, regularity, or uniformity.

An erratic heartbeat.

American Heritage

Deviating from the normal, conventional, or customary course; eccentric; queer.

Webster's New World

Designating a boulder or rock formation transported some distance from its original source, as by a glacier.

Webster's New World

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

Henry has been getting erratic scores on his tests: 40% last week, but 98% this week.

Wiktionary

Synonyms:

Antonyms:

noun

A rock fragment that has been transported by ice to a location other than its place of origin and that may range in size from a pebble to a large boulder.

American Heritage

An erratic person.

Webster's New World

Synonyms:

Other Word Forms of Erratic

Noun

Singular:

erratic

Plural:

erratics

Origin of Erratic

Middle English erratik from Old French erratique from Latin errāticus from errāre to wander ers- in Indo-European roots

From American Heritage Dictionary of the English Language, 5th Edition
From Old French erratique, from Latin erraticus.

From Wiktionary