ferro-Related entries & more
before vowels ferr-, word-forming element indicating the presence of or derivation from iron, from Latin ferro-, combining form of ferrum "iron," which is of unknown origin. Possibly of Semitic origin, via Etruscan [Klein]; Watkins suggests "possibly borrowed (via Etruscan) from the same obscure source as OE bræs "brass." Also sometimes especially indicative of the presence of iron in the ferrous state; ferri- indicating iron in the ferric state.
-iumRelated entries & more
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).