kilter

kilter · noun¹

A variant of dialectal kelter (“good condition, order”), of unknown origin; possibly related to kilt (“to gather up (skirts) around the body”) (cognate with Danish kilte (“to tuck”)), or Scots kilt (“proper way of doing something, knack”) (probably from kilt (“a slope; a tilt”), possibly a variant of English tilt). In the 19th century, kelter was the more common form in the United Kingdom, while kilter was more common in the United States. Due to the influence of the latter, kilter is now the more prevalent form in all English varieties.

kilter · noun²

Probably a variant of dialectal kelter (“odds and ends; litter, rubbish”); further etymology unknown.

First known use, by meaning

• from 17th c. Chiefly in out of kilter: (good) condition, form, or order; fettle.