hafnium, Hf, atomic number
(noun) a grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons
Source: WordNet® 3.1
hafnium (uncountable)
A chemical element (symbol Hf) with an atomic number of 72: a lustrous, silvery-grey tetravalent transition metal.
• celtium (former name)
Source: Wiktionary
22 December 2024
(noun) (plural) spectacles that are darkened or polarized to protect the eyes from the glare of the sun; “he was wearing a pair of mirrored shades”
The word “coffee” entered the English language in 1582 via the Dutch “koffie,” borrowed from the Ottoman Turkish “kahve,” borrowed in turn from the Arabic “qahwah.” The Arabic word qahwah was traditionally held to refer to a type of wine.
