51吃瓜 of the Day
selenography
noun
the branch of astronomy that deals with the charting of the moon's surface.
More about selenography
Selenography 鈥渢he branch of astronomy that charts the moon鈥檚 surface鈥� is a compound of seleno- and -graphy. The former comes from Ancient Greek 蝉别濒岣梟脓 鈥渕oon,鈥� while the latter ultimately comes from Ancient Greek 驳谤补辫丑岣� 鈥渨riting.鈥� The noun 蝉别濒岣梟脓 is also the source of Selene, the moon goddess, and comes from 蝉茅濒补蝉 鈥渟hine,鈥� plus the noun-forming suffix -苍脓, making 蝉别濒岣梟脓 literally mean 鈥渟hinier, lighter.鈥� A similar formation appears in Latin with 濒奴苍补 鈥渕oon,鈥� contracted from the root luc- 鈥渓ight鈥� and the suffix -na. Take care not to confuse Selene with the name Celine, from either Latin Caelina (from caelum 鈥渉eaven鈥�) or French Marceline (from Latin Marcus). Selenography was first recorded in English in the 1640s.
how is selenography used?
In the history of Selenography, John Henry Maedler holds a distinguished place. He was the very first to publish a large map of the lunar surface; and his map was a good one, very accurate, and beautifully executed.
The selenography of one side of the moon is much better known to us than the geography of the earth. Our maps of the moon are far more perfect than those of the earth…
gallantly
adverb
in a courageous, spirited, or noble-minded way.
More about gallantly
Gallantly 鈥渋n a courageous way鈥� is a compound of the adjective gallant and the adverb-forming suffix -ly. The -ant element in gallant is a telltale sign of the word鈥檚 origin; -ant is a common marker appearing in both French and Latin that shows that a word was originally a present participle. Just as tenant means 鈥渉olding鈥� in Middle French and radiant comes from Latin 谤补诲颈腻苍蝉 鈥渟丑颈苍颈苍驳,鈥� gallant was the Old French present participle, meaning 鈥渁musing oneself,鈥� of the verb galer 鈥渢o amuse oneself, make merry.鈥� Because of the sound change from w to g (or gu) when French borrowed Germanic words (usually from Frankish), gallant is a distant relative of English wealth, well, and will. For another example of this w/g contrast, compare the recent 51吃瓜 of the Day guerdon. Gallantly was first recorded in English in the mid-16th century.
how is gallantly used?
Sen. Daniel Inouye, the second-longest serving senator in U.S. history, was remembered Thursday as a man who gallantly defended his country on the battlefield and gracefully sought to better it during the 50-plus years he represented his beloved state of Hawaii.
Camo毛ns lost an eye in the service of his king as gallantly as Cervantes lost a hand at Lepanto. It is an undisputed fact that during the siege of Paris there was scarcely a painter or poet or sculptor or musician who did not enlist in the army and do battle for his country at bitter need 鈥�
hadron
noun
any elementary particle that is subject to the interaction responsible for the short-range attractive force that holds together the nucleus of the atom.
More about hadron
Hadron 鈥渁n elementary particle subject to the strong nuclear force鈥� is a coinage based on Ancient Greek 丑补诲谤贸蝉 鈥渢hick, bulky鈥� or 鈥渟trong, great,鈥� with the suffix -on (clipped from ion). Hadron is not related to the name Hadrian, which comes from a Roman place name that is also the source of Adriatic. Some linguists connect 丑补诲谤贸蝉 to Old English 蝉忙诲 鈥渟ated, full鈥� or 鈥渉eavy, weary鈥� (compare modern English sad) on the grounds that Ancient Greek h tends to correspond to English s. If this connection is valid, that also makes 丑补诲谤贸蝉 a relative of Latin satis 鈥渆nough鈥� (found in asset, satiate, and satisfy) and satur 鈥渇ull, well-fed鈥� (found in satire and saturate). Russian physicist Lev Okun created hadron in 1962 as a counterpart of lepton (from Ancient Greek 濒别辫迟贸蝉 鈥渟mall, slight鈥�).
how is hadron used?
Protons are the only hadrons known to be stable in isolation鈥攏eutrons are stable only when they are incorporated into atomic nuclei. All other hadrons form only fleetingly, from the collision of other particles, and decay in a fraction of a second. So the LHC [Large Hadron Collider] creates new kinds of hadron by causing high-energy, head-on collisions between protons.
Quarks are elementary particles that usually combine in groups of twos and threes to form hadrons such as the protons and neutrons that make up atomic nuclei. More rarely, however, they can also combine into four-quark and five-quark particles, or tetraquarks and pentaquarks.