Trivial name for example, hydrogen ("water-producing"), oxygen ("acid-producing"), nitrogen ("soda-producing"), bromine ("stink"), and argon ("no reaction") were based on Greek roots, while the names of iodine and chlorine were derived from the Greek words for their characteristic colors. Indium, rubidium, and thallium were similarly named for the colors of particular lines in their emission spectra. Iridium, which forms compounds of many different colors, takes its name from "iris", the Latin for "rainbow". The noble gases have all been named for their origin or properties. Helium comes from the Greek "helios", meaning "sun" because it was first detected as a line in the
Tre- (place name element) was evidence of political and linguistic distinction at some time from the 8th to 11th centuries. Tre- (place name element) Tre- is a place name element of Celtic origin meaning "hamlet, farmstead, estate", etc. which survives mainly in Wales and in the Southwest of England (almost exclusively in Cornwall). The manor of Trefusis was thus originally held before the Norman Conquest of 1066 by an Anglo-Saxon named "Fusis" or similar, thus "Farmstead of Fusis". The Cornish place-name beginning "Tre-" may be compared to the Cornish place-name beginning "Bod-" and the place-name endings "-worthy" and "-cot" in Devon, and "-ham" and