There is a story doing the rounds on social media that the game “tag” derives from “touch and go”. It doesn’t. That is, at best, a backronym. The word “tick” dates back to the mid 15th century as a word to mean “to tap lightly”, and similarly the Middle English word “tek”. By 1721, the word “tig” was being used in Scotland to describe the children’s game, and by 1738, the word “tag” had been recorded.
Words made up as acronyms were not common in the English language before the 20th century, so if you see stories ascribing the origin of a word to a pre-20th century acronym, there is a good chance that it’s either nonsense or a backronym, where someone takes a word and reverse fits it to make it appear like an acronym, like Oscar Deutch who named his cinema company Odeon, as in the old Greek word for an amphithetre, but declared it stood for “Oscar Deutsch Entertains Our Nation”.
There are plenty of these false acronyms around, like the old stories that “news” derives from North, East, West, South, that “cop” comes from “Constable on Patrol”, and the early days of email saw a story that “golf” was Gentlemen Only, Ladies Forbidden. One of the first fake acronym I heard was back when I was at primary school when we heard that “posh” came from Port Out, Starboard Home. That story was so widely believed that it even features in the film Chitty Chitty Bang Bang. In case you were wondering, the word posh meant “money” back in 1830, possibly from the Romany “posh-houri” or half pence. By the late 19th century, posh meant a dandy, and by 1914 was used in its current form. However, the “port out starboard home” description seems to date from 1935, long after the word was in use.
So, if you “tag friends” on Facebook, rest assured it’s not a case of touch and go, more of a light tap.