capital of France, from Gallo-Latin Lutetia Parisorum (in Late Latin also Parisii), name of a fortified town of the Gaulish tribe of the Parisii, who had a capital there; literally "Parisian swamps" (see Lutetian).
The tribal name is of unknown origin, but it is traditionally derived from a Celtic par "boat" (perhaps related to Greek baris; see barge (n.)), hence the ship on the city's coat of arms.
word-forming element in chemistry, used to coin element names, from Latin adjectival suffix -ium (neuter of -ius), which formed metal names in Latin (ferrum "iron," aurum "gold," etc.). In late 18c chemists began to pay attention to the naming of their substances with words that indicate their chemical properties. Berzelius in 1811 proposed forming all element names in Modern Latin. As the names of some recently discovered metallic elements already were in Latin form (uranium, chromium, borium, etc.), the pattern of naming metallic elements in -ium or -um was maintained (in cadmium, lithium, plutonium, etc.; helium is an anomaly).
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Definitions of lutetium from WordNet
a trivalent metallic element of the rare earth group; usually occurs in association with yttrium;