Gordon Gould coined the acronym LASER before the first one was built. Ted Maiman originally called his invention an "atomic radio light". Bell Labs pushed the phrase "optical maser" for a few of the first years.
Damn, I'm sure glad we ending up with LASER as the name. Imagine: "Atomic Radio Light Forums". "Sawnu Atomic Radio Lights". Guess it could be abbreviated too. Wicked ARLs, ARL Discord .lol
Its my favorite piece of nerd lore, that "Phaser" from Star Trek is derived from "Photon Maser" (Although to technically since masers use microwaves thats still photons) because "Laser" wasn't a common enough word yet. But in the early original series Phasers were essentially just lasers.