What's in a Name — Miraculous Ladybug
Tikki: according to Thomas Astruc, it's supposed to mean "happiness" in a language he can't remember. After doing some research, I believe he was going for the Greek word "eftychia". Interestingly enough, this word had the meaning of "good luck" in Ancient Greek, and is ultimately derived from the Ancient Greek word "tyche", meaning "luck, fortune", which was also the name of the Greek goddess of luck, equivalent to the Roman goddess Fortuna.
Plagg: from English "plague".
Trixx: from English "tricks".
Wayzz: either from English "wise" or "ways".
Pollen: self-explainatory.
Nooroo: either from the Japanese pronunciation of English "null", as this was his name in previous drafts, or from an Arabic word meaning "light". That, or "neuro-".
Duusu: either from French "douce" ("sweet", F), Luxembourgish "duuss" ("gentle, tender, soft") or various Slavic words for "soul", like Polish "dusza" or Czech "duše".
Mullo: from French "mulot", meaning "field mouse". It was initially supposed to be Toppo, from the Italian word for mouse ("topo"), but this was changed during development. This latter name did, however, still end up being used once in the English dub of Kwamibuster.
Stompp: self-explainatory.
Roarr: self-explainatory.
Longg: from Mandarin "long", meaning "dragon".
Sass: most likely from the hissing sound a snake makes.
Kaalki: in reference to Kalki, the tenth avatar of the god Vishnu, which is depicted as a white horse.
Ziggy: most likely from German "Zeige", meaning "goat". Is also a reference to Ziggy Stardust.
Xuppu: in reference to Xu Sheng, a character from "Journey to the West" who initially rejects the existence of Sun Wukong before becoming a devotee of his in the story "The Great Sage, Heaven's Equal" by Pu Songling. The name is a blending of the character's name and the author's.
Barkk: self-explainatory.
Orikko: from "cocorico", which is the French word for the sound a rooster makes.
Daizzi: in reference to the pig character Zhu Baije from "Journey to the West", who is often called "Dai Zi", meaning "idiot".
Liiri: from Albanian "liri", meaning "freedom".