-ous
/-əs/suffix
Elementary
1
possession of
2
presence of a quality in any degree (typically an abundance)
3
relation or pertinence to
4
Used in chemical nomenclature to name chemical compounds in which a specified chemical element has a lower oxidation number than in the equivalent compound whose name ends in the suffix -ic. For example sulphuric acid (H₂SO₄) has more oxygen atoms per molecule than sulphurous acid (H₂SO₃). See Inorganic nomenclature.