erratic

• erratick, erraticke, erratique (all obsolete)

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

• IPA^(key): /ɪˈɹætɪk/

• Audio (AU)

  (file)

• Rhymes: -ætɪk

erratic (comparative more erratic, superlative most erratic)

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

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

2. Deviating from normal opinions or actions; eccentric; odd.

   erratic conduct

• consistent

erratic (plural erratics)

1. (geology) A rock moved from one location to another, usually by a glacier.
   • 2003, Bill Bryson, A Short History of Nearly Everything, BCA, page 372:

     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.

   • 2015 May 4, Dominick Tyler, “10 UK landscape features that you’ve probably never heard of”, in The Guardian‎:

     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”.

2. Anything that has erratic characteristics.

• (glaciers): dropstone

• Cartier, cartier, cirrate, rice rat