casing

Etymology

It is formed from English case² + -ing, from the verb case, to put in a case.^[2][3][4][5] That verb comes from the noun,^[2] which is from Anglo-Norman case, a variant of Anglo-Norman chas and Old French chasce, recorded for a reliquary or a box,^[2] from Latin capsa (“cylindrical case for holding books; receptacle”),^[2][5] probably from capiō (“to take, hold”).^[2][4]

Earliest recorded meaning

The act of casing something: 1575, in G. Gascoigne's Noble Arte of Venerie.^[2][3] Dictionary.com dates the word 1565–75.^[5]

Semantic evolution

The verbal noun soon had an adjective beside it, "that encases", in Shakespeare's Macbeth (before 1616).^[2] The concrete sense, the thing that encloses, came much later: in building from 1791, in J. Smeaton's Narrative of the Building,^[2][4] and generally from 1839, in a book on the marine steam engine.^[2][3] Technical uses, especially in American mining, followed in 1869, and the frame round a door or window in 1873, first in American use.^[2] The slang sense, looking over a place before robbing it, comes from the verb case in the same meaning, which the Oxford English Dictionary suggests may be a pun on watch, as in watch-case.^[2] Green's Dictionary of Slang finds it in D. Hammett in 1926,^[6] and by 1942 pitchmen used it for sizing up their likely customers.^[6]

Timeline

• 1575 – the action of putting into a case.^[2][3]
• before 1616 – adjective, that encases or encloses.^[2]
• 1791 – a covering in building.^[2][4]
• 1839 – something that encases, a covering.^[2][3]
• 1869 – technical uses, especially in American mining.^[2]
• 1873 – the framing round a door or window, first in American use.^[2]
• 1926 – slang, the inspection of a place before a robbery.^[6] The Oxford English Dictionary first has it in 1928.^[2]

Meanings

Noun

1. An outer cover or shell that protects or holds something: the plastic casing of the router.^[7][4][2]
2. The frame or molding around a door or window.^[7][4][2]
3. A metal pipe that lines a water, oil or gas well.^[7][4]
4. A skin-like case for sausage or other processed meat, made from animal intestines or from cellulose.^[7][4]
5. A thin layer of glass fused onto glass of another kind or colour.^[4]
6. A narrow channel for a rod or cord, made by folding over fabric, as in a curtain or waistband.^[7]
7. (slang, originally US) The inspection of a place or person to judge how open it is to robbery.^[6][2]

Related words

• case
• capsule
• encase

Usage notes

The Oxford English Dictionary records separately, from the Promptorium Parvulorum of 1516, a noun casing with a short vowel, /ˈkasɪŋ/, which it takes as probably a Scandinavian borrowing, comparing Danish kassen and kasing, regional in Jutland for the dried dung of farm animals, used as fuel.^[2]

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q r s t u v Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d e f g h i Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
5. ^ a b c Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
6. ^ a b c d Green, Jonathon (2010), Green's Dictionary of Slang, London: Chambers; digital ed. 2016–, https://greensdictofslang.com
7. ^ a b c d e The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt