# molybdenum

> English word · Noun · IPA /məˈlɪbdɪnəm/ · frequency rank #39,918

## Definitions
1. A chemical element (symbol Mo) with an atomic number of 42: a silvery metal, not found as a free element, used in steel alloys.
2. A single atom of this element.

## Etymology
From New Latin molybdaenum, from molybdaena (“any of various substances resembling lead”), from Ancient Greek μολύβδαινα (molúbdaina, “a plummet, piece of lead”), from μόλυβδος (mólubdos, “lead; graphite”), from an Anatolian word cognate with Lydian 𐤪𐤠𐤭𐤦𐤥𐤣𐤠 (mariwda, “dark”), from Proto-Indo-European *morkʷ-iyo-, from a root *morkʷ- (“dark”), cognate with English murk. Cf. Latin plumbum nigrum 'lead'. The suffix is + -um (“a chemical element”).
Attested since the last quarter of 18th century.

## Common misspellings (16)
`mloybdenum`, `mmolybdenum`, `molbydenum`, `mollybdenum`, `molybbdenum`, `molybddenum`, `molybdenmu`, `molybdennum`, `molybdenumm`, `molybdeunm`, `molybdneum`, `molybednum`, `molydbenum`, `molyybdenum`, `moylbdenum`, `omlybdenum`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/molybdenum