molybdenum (Mo)
Obsolete term for the chemical element molybdenum; replaced by the loanword モリブデン in modern Japanese.
See also: モリブデン
In old chemistry books, molybdenum is sometimes written as 水鉛.
molybdenite
The exact derivation is uncertain; the kanji 水 (water) and 鉛 (lead) may reflect early descriptive naming, but the term is now obsolete.