This phrase is used to indicate that someone (or thing) bears an uncanny resemblance to someone (or something) else.
It is uncanny how many times TOWT gets mistaken for someone else, often in the most unlikely of situations, including once for someone whom the observer had thought was dead! She must have a whole army of dopplegangers. Even I was once mistaken for Jeremy Irons whilst wandering through the streets of Copenhagen. But where does this slightly unsavoury phrase come from?
As usual, there is no definitive explanation but the most likely centres around the concept that someone is so similar that they could have been spat out of their mouth. This allusion was certainly doing the rounds by the late 17th century. George Farquhar’s comedy of 1689, Love and a bottle, contains the line, “Poor child! he’s as like his own dadda as if he were spit out of his mouth”.
Whilst it is dangerous to seek confirmation from other languages – after all, the concept may have been imported from English – nonetheless the French have the expression, “C’est le portrait craché de son père” (he’s the spitting portrait of his father) and the Norwegians “som snytt ut av nesen paa” (as blown out of the nose of).
So we may hazard that spit means closeness or similarity, a usage confirmed in The Newgate Calendar of 1824-26, “A daughter…the very spit of the old captain” and in several other sources during that century, often in the form dead spit. Possibly, though, the recognition of the original meaning of spit was on the wane and so to reinforce the concept “and image” was added. Certainly by 1895 in E.Castle’s Lieutenant of Searthey we find, “She’s like the poor lady that’s dead and gone, the spit an’ image she is” and it is just a small step to elide the two concepts into a spitting image, something that certainly had happened, at least in representations of the common vernacular at the start of the twentieth century.
An alternative phrase used to convey the same concept is dead ringer. The derivation of this phrase is more straightforward and has nothing to do with campanology. A ringer is a horse which was switched for another of a similar appearance in order to hoodwink the bookmakers – most of the horses that I bet on seem to have been the subject of such a switch.
The term was part of the vocabulary of the North American horse-racing community in the 19th century and is helpfully defined for us by the Manitoba Free Press of 1882, “A horse that is taken through the country and trotted under a false name and pedigree is called a ‘ringer.‘”
In English the adjective “dead” is rather a portmanteau one and is used in many different contexts with many different meanings and connotations. Of course, the meaning most commonly ascribed to it is being no longer alive, no more, deceased and so on. But it also has the meaning of exactly or precisely when used, for example, in conjunction with centre meaning precisely in the middle. Its usage in association with a ringer serves to emphasis the exactitude of the match.
Dead ringer is the spitting image of spitting image and as someone who is inclined to resist Americanisms when there is a good alternative it is the latter I will stick with.
So now we know!