The Greek and Latin word for the hardest imaginable substance, whether applied to a legendary stone or an actual substance, such as diamond, was adamas. Latin poets used the term figuratively for things lasting, firm, or unbending, and the adjective adamantinus was used in similar contexts. The English noun adamant (meaning “an unbreakable or extremely hard substance”), as well as the adjective adamant (meaning “inflexible” or “unyielding”), came from adamas. Adamantine, which also has such figurative uses as “rigid,” “firm,” and “unyielding,” came from adamantinus.Adamas is actually the source of diamond as well. Diamas, the Latin term for diamond, was an alteration of adamas.

Test Your Memory: Fill in the blank in this sentence from our November 22nd Word of the Day: “The explosion of a supernova leaves behind a ______ from which, upon cooling, new stars and planets may develop.”The answer is …