lanthanide

Plural: lanthanides

Noun

• any element of the lanthanide series (atomic numbers 57 through 71)
• Any of the 15 rare earth elements from lanthanum to lutetium in the periodic table; because their outermost orbitals are not filled, they have very similar chemistry; below them are the actinides.
• Any of the 14 rare earth elements from lanthanum to ytterbium (lutetium is excluded by some authors as it is a d-block rather than an f-block element).
• Any of the 14 rare earth elements from cerium to lutetium (lanthanum having been excluded because it was thought to be a d-block element in the past).

Synonyms

lanthanate, lanthanoid, lanthanon, rare earth, rare-earth element

Related Words

cerium, dysprosium, erbium, europium, gadolinium, holmium, lanthanum, lutetium, neodymium, praseodymium, promethium, samarium, terbium, thulium, ytterbium