Etymology
Advertisement
Oneida 

Iroquois people of upper N.Y. state (they later moved in part to Wisconsin), 1660s, named for their principal settlement, the name of which is from Oneida onenyote', literally "erected stone," containing -neny- "stone" and -ot- "to stand."

Related entries & more 
Advertisement
Onondaga 

a people of the Iroquois confederacy, 1680s, named for its principal settlement, from Onondaga onontake, literally "on the hill."

Related entries & more 
Oort cloud (n.)

in reference to a hypothetical cloud of small objects beyond Pluto that become comets, proposed 1949 by Dutch astronomer Jan Hendrick Oort (1900-1992), and named for him by 1968.

Related entries & more 
Ophelia 

fem. proper name, from Greek opheleia "help, aid," from ophelein "to help, aid, assist," ophelos "advantage, help," from PIE root *obhel- "to avail" (source also of Armenian avelum "increase, abound").

Related entries & more 
Ophir 
name of a place mentioned in Old Testament as a source for fine gold; location still unknown. Hence Ophir-gold (1610s).
Related entries & more 
Advertisement
Orangemen (n.)

1796 in reference to members of a secret politico-religious society founded 1795 in Belfast to promote Protestant power in Northern Ireland, named for William of Orange (who became King William III of England and triumphed in Ireland at the head of a Protestant army at the Battle of the Boyne), of the German House of Nassau. His cousins and their descendants constitute the royal line of Holland.

The name is from the town of Orange on the Rhone in France, which became part of the Nassau principality in 1530. Its Roman name was Arausio, which is said in 19c. sources to be from aura "a breeze" and a reference to the north winds which rush down the valley, but perhaps this is folk etymology of a Celtic word. The name subsequently was corrupted to Auranche, then Orange.

The town has no obvious association with the fruit other than being on the road from Marseilles to Paris, along which masses of oranges were transported to northern France and beyond. In this roundabout way the political/religious movement of Northern Irish Protestantism acquired an association with the color orange, the Irish national flag acquired its orange band, and Syracuse University in New York state acquired its "Otto the Orange" mascot.

Related entries & more 
Ordovician (adj.)

in reference to the geological period following the Cambrian and preceding the Silurian, 1879, coined by English geologist Charles Lapworth (1842-1920) from Latin Ordovices, name of an ancient British tribe in North Wales. The period was so called because rocks from it first were studied extensively in the region around Bala in North Wales. The tribe's name is Celtic, literally "those who fight with hammers," from Celtic base *ordo "hammer" + PIE root *weik- (3) "to fight, conquer." The geological period at first was considered as either part of the Silurian or the Cambrian, and Lapworth's proposed name took time to win universal acceptance, not receiving international approval as an official period until 1960.

Related entries & more 
Oregon 

1765 as the name of a large river in the west of North America, probably the modern Columbia; a word of uncertain and disputed origin. It seems to be of Algonquian origin. In the U.S. it came to be applied to the northwest generally. From 1848 as the name of a U.S. territory, admitted as a state 1859. The Oregon in Pennsylvania was named for the western territory. Related: Oregonian.

Related entries & more 
Oreo (n.)

 type of cookie (made by Nabisco), 1912; the source of the name has been forgotten. As a derogatory word for "black person felt to have a 'white' mentality," 1968, African-American vernacular, from the snack cookies, which consist of dark chocolate wafers and white sugar cream filling (hence "brown outside, white inside"). Compare radish-communist (1920), one who proclaims enthusiasm for the Party but privately opposes it, on the notion of red outside, white inside.

Related entries & more 
Orion 

conspicuous constellation containing seven bright starts in a distinctive pattern, late 14c., orioun, ultimately from Greek Oriōn, Oariōn, name of a giant hunter in Greek mythology, loved by Aurora, slain by Artemis, a name of unknown origin, though some speculate on Akkadian Uru-anna "the Light of Heaven."

Another Greek name for the constellation was Kandaon, a title of Ares, god of war, and the star pattern is represented in many cultures as a giant (such as Old Irish Caomai "the Armed King," Old Norse Orwandil, Old Saxon Ebuðrung). A Mesopotamian text from 1700 B.C.E. calls it The True Shepherd of Anu. The Orionid meteors, which appear to radiate from the constellation, are so called by 1876.

I this day discovered a new particular of my own ignorance of things which I ought to have known these thirty years — One clear morning about a fortnight since I remarked from my bed-chamber window a certain group of stars forming a Constellation which I had not before observed and of which I knew not the name — I marked down their positions on a slip of paper with a view to remember them hereafter and to ascertain what they were — This day on looking into the Abridgment of La Lande's Astronomy, one of the first figures that struck my eye in the plates was that identical Constellation — It was Orion — That I should have lived nearly fifty years without knowing him, shews too clearly what sort of observer I have been. [John Quincy Adams, diary entry for Nov. 18, 1813, St. Petersburg, Russia]
Related entries & more 

Page 3