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-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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of -ous

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Pachydac′tyl, -ous, having thick digits; Pach′yderm, thick-skinned—n. one of an order of non-ruminant, hoofed mammals, thick-skinned, as the elephant:—pl.

From Chambers's Twentieth Century Dictionary (part 3 of 4: N-R) by Various

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 Sargeaunt, John

The affixes -ous and sub- refer to the compounds containing more of the positive element, -ic and per- to those containing less.

From Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1 "Châtelet" to "Chicago" by Various

Agamic -ous: reproducing without union with a male.

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

Monotrocha -ous: Hymenoptera in which the trochanters are single: having legs in which the trochanter is one-jointed.

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