When the word omelette was first used in an early seventeenth century French-English dictionary, it was spelled omelet, and later forms included ormlet, omlet, omlette, and omellette. As you may surmise, it was borrowed from French, where it had a very interesting history. The word was metathesized (the m and l switched places) from French alemette, which was a diminutive of the word for "knife blade", alemele. Before that, it's thought that alemele was an accidental rebracketing of la lemelle (meaning "small plate") because of people mistaking it with l'amelle. Finally, lemelle derives from the Latin noun lamina, also "thin plate" (with that thought to trace to the Proot-Indo-European reconstruction stelh, "broad"). Usage of the word omelette rapidly increased in the early 2000s and peaked in 2017.
Hello! I'm Adam Aleksic, a sophomore studying government and linguistics at Harvard University, where I co-founded the Harvard Undergraduate Linguistics Society. In addition to etymology, I also really enjoy politics, vexillology, geography, board games, conlanging, and law.