-ine (?; 104). 1. (Chem.) A suffix, indicating that those substances of whose names it is a part are basic, in their nature, i.e. contain a basic nitrogen group.
[1913 Webster +PJC]

&hand_; All organic bases, and basic substances (especially nitrogenous substances), are systematically written with the termination -ine; as, quinine, pyridine, morphine, guanidine, etc. Certain substances containing nitrogen though with net neutral character (as certain amino acids) also end in -ine, such valine and glycine. All indifferent and neutral substances, as proteids, glycerides, glucosides, etc., should commonly be spelled with -in; as, gelatin, amygdalin, etc. This rule has no application to those numerous commercial or popular names with the termination -ine; as, gasoline, vaseline, etc.
[1913 Webster +PJC]

2. (Organ. Chem.) A suffix, formerly used to indicate hydrocarbons of the second degree of unsaturation; i. e., members of the acetyline series; as, hexine, heptine, etc., but now superseded by the ending -yne, as in propyne.
[1913 Webster +PJC]