Go to 'thermo-' entry Go to 'dino-' entry Go to 'chondro-' entry Go to 'aero-' entry Go to '-logy' entry Go to 'thaumato-' entry Go to 'nano-' entry Go to '-sophy' entry Go to 'bucco-' entry Go to '-ism' entry Go to '-lysis' entry Go to 'galacto-' entry Go to '-anthropy' entry Go to 'pneumo-' entry Go to '-ploitation' entry Go to '-lithic' entry Go to '-sepalous' entry Go to 'onco-' entry Go to '-parous' entry Go to 'dermato-' entry Go to 'multi-' entry Go to 'dodeca-' entry Go to '-zoon' entry Go to 'vermi-' entry Go to 'crystallo-' entry Go to 'biblio-' entry Go to 'eco-' entry Go to 'juxta-' entry Go to 'facio-' entry
Affixes: the building blocks of English
Affixes: the building blocks of English

-ous Also -eous, -ious, and -ulous.

Forming adjectives.

[Latin -osus.]

The -ous ending is extremely common and is a standard way of forming adjectives, either from words of French or Latin origin (in the latter case usually from nouns ending in -us), or from native English nouns. Examples include cancerous, dangerous, generous, libellous, mountainous, ominous, poisonous, thunderous, and wondrous.

The form -ious is a variant from Latin -iosus, often via French -ieux (cautious, curious, delirious, mysterious, precious, spacious, vivacious); examples in -eous are from Latin words ending in -eus (aqueous, calcareous, extraneous, instantaneous, simultaneous, vitreous). Those in -ulous are usually from Latin words ending in -ulosus or -ulus (fabulous, miraculous, populous, ridiculous).

The -ous ending frequently appears in compound suffixes, separate entries for which are at -aceous, -androus, -ferous, -gerous, -gynous, and -parous. See also -cephalic (for -cephalous), -mer (for -merous), -phagy (for -phagous), -phile (for -philous), -phore (for -phorous), and -vore (for -vorous).

In chemistry, -ous specifically denotes an element having a lower combining power: cuprous, ferrous, nitrous, sulphurous. In such cases, the higher valency is marked by -ic.

See also -ose1.

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