-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 ).

---

-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

---

Etymology

Origin of -ous

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

Example Sentences

See Examples For:

-ous

Hydradephaga; -ous: applied to aquatic, predatory pentamerous beetles with filiform antennae: see adephagous.

From Explanation of Terms Used in Entomology by John. B. Smith

Rugose -ous: wrinkled: with irregular waved elevated lines.

From Explanation of Terms Used in Entomology by John. B. Smith

A ternary acid with the termination -ic gives a salt with the name ending in -ate, while an acid with termination -ous gives a salt with the name ending in -ite.

From An Elementary Study of Chemistry by William McPherson

Some words ending in -ous are not of this class.

From Society for Pure English Tract 4 The Pronunciation of English Words Derived from the Latin by John Sargeaunt

In cases where more than two acids are known, use is made of prefixes in addition to the two suffixes -icand -ous.

From An Elementary Study of Chemistry by William McPherson