Since the 14th century1,2 people have declared things to be dead as doornails. It makes sense as doornails are indeed dead inanimate objects, but then so are diamonds, doughnuts, and doorknobs. So why were doornails chosen of all things? What is the origin of dead as a doornail?
There are 2 main theories as to why doornails where the object of choice in this age-old phrase.
Theory 1: Doornails were hit with a knocker so many times they had to be dead!
Some say that the doornail in the phrase refers to the nail on which the knocker was struck. It was placed there to make a clearer knocking sound. One idea is that this nail was considered to be dead because the usual metallic ring of the nail was deadened to a dull knock as the sound was diffused into the door. Another slightly black-humoured theory is that the doornail may have been said to be dead because of the number of times the knocker struck it on its head!
Etymologists tend to favour theory 2 however:
Theory 2: A dead nail was one that could not be reused
In carpentry, when a nail is said to be “dead”, it means that it is so well hammered into the door that it cannot be taken out to be reused. Doornails in particular were famous for being securely hammered into doors and “clinched”, a process which involved any protruding bit of the nail being hammered flat over the side of the door so that they were well and truly in place. This was done to strengthen the door.
This theory suggests that “dead as a doornail” refers to these clinched nails which found their final resting place in doors.
References
- Langland, W. 1350. The Vision of Piers Plowman. Everyman Paperbacks; 2 edition .
- Shakespeare W. 1592. King Henry VI, Part 2. Act 4, Scene 10.
- Morris W. 1988. The Morris Dictionary of Word and Phrase Origins. Collins Reference; 2 Sub edition
Related articles
- Why do we say someone is flying off the handle?
- Why do we say a celebrity is in the limelight?
- Why do we say we put money in the kitty?
Related Products
Note:
This site is working in affiliation with Amazon.com (for USA visitors) and The Nutri Centre (for UK visitors). If you like a product that was recommended anywhere on this website, please consider buying these products via the links on this site, to help keep this website running. Thanks 
Haha, cool, thanks for the knowledge.
This comment is just to say thanks for posting this! i dont comment usually, but when i do it is often for some thing quite good.
I always thought it was “dead as a doormouse” haha I always get my phrases confused!
Good to know! And naturally, thank you to your sweat and effort writing this!
I read many years ago that in very early times before iron nails were in common use, doors were constructed with wooden pegs (nails or dowels) made from the dead and very strong heartwood of a tree, hence ‘dead as a doornail’. Could this be a valid explanation? Certainly things such as roof timbers were fastened with large wooden pegs – I have some in my own cottage roof!
Epic
I often wondered exactly what this phrase meant and what the origin is, I always thought that “dead as a coffin nail” would make more sense. haha.