- a suffix, occurring in adjectives of Greek and Latin origin, meaning “pertaining to,” and (in nouns thence derived) also imitated in English (coffin; cousin, etc.).
Origin of -in1
- a noun suffix used in a special manner in chemical and mineralogical nomenclature (glycerin; acetin, etc.). In spelling, usage wavers between -in and -ine. In chemistry a certain distinction of use is attempted, basic substances having the termination -ine rather than -in (aconitine; aniline, etc.), and -in being restricted to certain neutral compounds, glycerides, glucosides, and proteids (albumin; palmitin, etc.), but this distinction is not always observed.
Origin of -in2
- a suffixal use of the adverb in, extracted from sit-in, forming compound nouns, usually from verbs, referring to organized protests through or in support of the named activity (kneel-in; chain-in; be-in) or, more generally, to any organized social or cultural activity (cook-in; sing-in).
- indicating a neutral organic compound, including proteins, glucosides, and glyceridesinsulin; digitoxin; tripalmitin
- indicating an enzyme in certain nonsystematic namespepsin
- indicating a pharmaceutical substancepenicillin; riboflavin; aspirin
- indicating a chemical substance in certain nonsystematic namescoumarin
Word Origin and History for -in
suffix attached to a verb, first attested 1960 with sit-in (which probably was influenced by sit-down strike); used first of protests, extended c.1965 to any gathering.
chemical suffix, usually indicating a neutral substance, antibiotic, vitamin, or hormone; see -ine (2).
- Neutral chemical compound:inulin.
- Variant of-ine