What does breech mean?
Breech is a noun referring primarily to the rear portion of something, most commonly the back end of a firearm's barrel, where the chamber sits and ammunition is loaded. A rifle or cannon may be described as muzzle-loading or breech-loading depending on whether it is charged from the front or the back. In medicine, particularly obstetrics, 'breech' describes a baby positioned bottom-first or feet-first in the womb rather than head-first; such a 'breech birth' often prompts careful monitoring or a planned caesarean section. An older, literary sense refers to the buttocks or hindquarters, surviving mainly in historical texts and set phrases. Though technical, the word carries real practical weight: soldiers, gunsmiths, and doctors all rely on it precisely, and confusing it with its homophone 'breach' can produce embarrassing errors. Its history traces back to Old English, sharing deep roots with words like 'breeches' — garments worn on the very part of the body the word once named.
The rear part of a firearm barrel, containing the chamber into which the cartridge or shell is loaded.
"He opened the breech and ejected the spent casing."
Commonly appears in compound terms such as 'breech-loading' and 'breechblock'.
A fetal position in which the baby's buttocks or feet, rather than the head, would be delivered first.
"An ultrasound confirmed the baby was in a breech position."
Usually used attributively in phrases like 'breech birth' or 'breech presentation'.
(archaic or literary) The buttocks or hindquarters of the body.
"In older novels, mischievous children were threatened with a whipping across the breech."
Largely obsolete in everyday speech; encountered mainly in historical literature.
Rare as a countable plural in modern usage; note that 'breeches' as a standalone word means knee-length trousers and functions as a separate lexical item.
"Historical accounts describe cleaning the breeches of several cannons after battle."
A single letter separates two very different words: you can be sued for a breach of trust, but no one has ever been sued over a breech.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of breech
Breech descends from the Old English 'brēc', originally the plural of 'brōc', meaning a covering for the loins and thighs — an early form of trousers or breeches. It shares this ancient root with the word 'breach' and with modern 'breeches' and dialectal 'britches'. Over time the sense narrowed and shifted from clothing on the lower body to the lower body itself, and then by extension to the rear end of objects such as guns.
Related word forms
How breech is actually used
Mostly used in technical contexts — military and firearms terminology, and medical/obstetric language. The anatomical sense ('buttocks') is archaic and now largely confined to literary use. Always spelled with double 'e', unlike its near-homophone 'breach'.
Easily confused with breech
A 'breach' is a violation or gap (as in a breach of contract or a breach in a wall), while 'breech' refers to the rear part of a gun or the lower body.