Today’s peeve: breech and breach are two different words.
Breech refers to the rear end of something, as in a breech-loading rifle, which is one where you don’t have to shove the powder and ball down the muzzle with a ramrod. Likewise, a breech birth is one where the arriving infant shows up rear-end first.
Breach, the noun, refers to a gap or a broken place, as in breach of contract, where some part of the contract has been broken, or a breach in the defenses, where some part of the literal or metaphorical wall has been taken down. A breaching charge is an explosive charge designed to take down a door or make a gap in a wall.
Breach, the verb, means to make a gap or a hole in something, usually by force. Don’t use breech when you mean this one, either. (There is a verb, to breech, but it means to promote a male child into trousers and out of toddler-wear – which used to be petticoats for both boys and girls. Like the petticoats, the verb itself isn’t all that common these days.)
So there you have it. Breach and breech – don’t use one when you mean the other. It makes the baby lexicographers cry.