Did you know that here in Catalunya a cheese and ham toasted sandwich (croque monsieur in French) is called a Bikini?
According to a reliable source it is known as a Bikini because of a bar in Barcelona of the same name in which they used to be very popular, so nothing to do with the swimwear or the atol. Apparently when the sandwich arrived in Spain from France the Bikini cafe was one of the first to serve it.
The bar still exists, but obviously at present is not open. It has been around longer than me, according to Google (62 years) and is one of Barcelona's best loved music venues.
At home I make my own version, using veggie 'ham' and often add in pickles or tomatoes etc...
And if I order one in a cafe I ask for it 'sin Jamon' - much to the servers surprise, and often get told its not a Bikini without the ham, just toasted cheese sandwich. 😊😊