This is Litchi chinensis, 荔枝, the lychee, sometimes called a “lychee nut” although it’s not nut-like at all. It’s more like a muscadine (tough skin, sweet juiciness) with a big seed in the middle. It’s one of the best things in life.
As I’m sure it was in the 1600s, when Michel Boym, a Polish Jesuit missionary, was studying them for his exhaustive work on Chinese botany. He also authored the first two dictionaries translating Chinese into European languages – Latin and French.
If you can’t find them fresh, try ’em frozen or canned. They’re great. The, uh, fruits, not the languages.