Word of the Day
Learn a new word every day! The Dictionary.com team of language experts carefully selects each Word of the Day to add some panache to your vocabulary.
(of high-altitude clouds) visible during the short night of the summer.
In noctilucent, the nocti- element comes from Latin nox, meaning “night.” Meanwhile, -lucent derives from Latin lucēre, “to shine,” from lux, meaning “light.” In this way, anything noctilucent is literally a night-light. Noctilucent was first recorded in English in the early 1690s, originally referring generally to things that shone in the dark. EXAMPLE OF NOCTILUCENT USED IN A SENTENCE A thin, threadlike patch of noctilucent clouds slowly came into view as the sun set behind the mountains.
dark or gloomy.
Stygian originally referred to Styx, one of the mythological rivers of the underworld. Ancient Greek Stýx likely shares an origin with several words relating to hatred, and the Greeks once believed that swearing on the river’s name created an unbreakable vow. Stygian was first recorded in English in the 1560s. EXAMPLE OF STYGIAN USED IN A SENTENCE The basement was a windowless, Stygian space, with only a single flickering fluorescent providing the weakest of light.
a small, burrowing rodent of the Pacific coastal region of North America, also known as the mountain beaver.
Sewellel is an adaptation of š-walál, a term from the Lower Chinook language of the Pacific Northwest that refers to a robe made of mountain beaver skins. When explorer Meriwether Lewis (of the Lewis and Clark expedition) heard š-walál, he misunderstood the term as referring to the mountain beaver itself and transcribed it as sewellel in 1806. EXAMPLE OF SEWELLEL USED IN A SENTENCE The sewellel poked its head out from its burrow and went off to forage for food.
a poisonous cloud of vapor produced by decaying organic matter.
Miasma derives from Ancient Greek míasma, meaning “pollution, stain.” The mías- element comes from the verb miaínein, “to pollute, stain,” while -ma is a common suffix that also appears in eczema, enigma, and stigma. Miasma was first recorded in English around 1660. EXAMPLE OF MIASMA USED IN A SENTENCE The impassable swamp was known for the many miasmata that drifted through the air, threatening to suffocate travelers.
a widespread and severe windstorm that moves rapidly along a fairly straight path and is associated with bands of rapidly moving thunderstorms.
Derecho means both “right” and “straight” in Spanish and comes from Latin dīrēctus, “straightened,” the source of English direct and adroit (through French droit). The Latin word for “right,” however, is dexter, which survives in ambidextrous. Derecho was first recorded in English in the late 1880s. EXAMPLE OF DERECHO USED IN A SENTENCE A long series of derechos and thunderstorms wended their way across the continent from early June through late August.
