-ous

American  

1. a suffix forming adjectives that have the general sense “possessing, full of ” a given quality (covetous; glorious; nervous; wondrous ); -ous and its variant -ious have often been used to Anglicize Latin adjectives with terminations that cannot be directly adapted into English (atrocious; contiguous; garrulous; obvious; stupendous ). As an adjective-forming suffix of neutral value, it regularly Anglicizes Greek and Latin adjectives derived without suffix from nouns and verbs; many such formations are productive combining forms in English, sometimes with a corresponding nominal combining form that has no suffix;

2. a suffix forming adjectival correspondents to the names of chemical elements; specialized, in opposition to like adjectives ending in -ic, to mean the lower of two possible valences (stannous chloride, SnCl 2 , and stannic chloride SnCl4 ).

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-ous British  

suffix

1. having, full of, or characterized by

   dangerous

   spacious

   languorous

2. (in chemistry) indicating that an element is chemically combined in the lower of two possible valency states Compare -ic

   ferrous

   stannous

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Etymology

Origin of -ous

Middle English < Anglo-French, Old French < Latin -ōsus; a doublet of -ose ¹

Example Sentences

In three previous men's marathon races, the largest margin of victory was 3.4 seconds by Ous Mellouli at London in 2012.

From Fox News • Aug. 4, 2021

He joined Ous Mellouli as the only Tunisians to win a gold in swimming.

From Seattle Times • Jul. 25, 2021

Ous, who until now had been staring mutely at his hands—each of which was tattooed with the name of a brother still in Mosul—looked up.

From The New Yorker • Jan. 29, 2017

“My dad works as a customs policeman, and the boss of his boss would call him up and say, ‘We didn’t hear Ous dedicate his medal to the president.’ ”

From New York Times • Mar. 5, 2011

They were distinguished by Marquette in 1673 as the "Ouchage" and "Autrechaha," and by Penicaut in 1719 as the "Huzzau," "Ous," and "Wawha."

From The Siouan Indians by McGee, W. J. (William John)