- A duplicate of the exact nature.
- A substitute for something.
- An imposter.
- She is a dead ringer of one of my friends. I in fact walked up to her at an event mistaking her for my friend.
- The car that is parked in that garage is a dead ringer of the car that my dad used to own a couple of years back.
- I used to have a gold necklace which had a dead ringer fake, you would never be able to find out which is the real one.
- I’ve heard that they change the crown jewels by their dead ringers so that they are protected from thieves. Is that true?
Since the 1900's a ringer is a term that is used for a horse that substitutes another one in order to confuse and subsequently defraud bookies before races. This term has been used in the year 1882 where it has been defined. It referred to another horse that was a very close duplicate. To ring means to exchange or to substitute something.
The relevance of the word 'dead' in this phrase means 'exact'. It is used similar to 'dead center' and 'dead shot'. This phrase is said to have been coined in the 19th century itself and was used in 1888.