I’m always so intrigued when words have come to mean the exact opposite of what they used to. And that, apparently, is what happened (metaphorically, at least) with ace.

Round about the year 1300, the word ace entered English. It was taken from the Latin as, which meant “one”–and is thought to be borrowed by Latin directly from the Greek eis, which means the same.

When it entered English, though, it wasn’t just to mean “one.” It was to particularly refer to the sides of dice with only one mark. Because of this, ace in Middle English was used metaphorically to mean “bad luck.” That stuck around for quite a while…until cards became popular.

In cards, ace was also used to the “one” card…but of course, in cards, that’s usually the highest, rather than the lowest. So as games switched popularity and cards began to rule the day, the metaphorical meaning of ace changed too. From “bad luck” to “top of the deck–the best.” This total flip had happened absolutely by the 18th century.

Phrases like “ace in the hole” came around by 1907; during World War I, ace became applied to the best pilots. From there, it moved into verb form–in the 1920s, you could ace in sports, which meant to score a point. In the 1950s, this sports sense was extended via student slang to mean, “score high marks.”

So there we have it–a four hundred year evolution from bad luck to the best, and then a slow move from being a noun to a verb. Ace has always meant “one”–but whether that’s a positive or negative has done an about-face.