I. noun — [ mass noun] 1.
[Chemistry] a crystalline compound with basic properties found in many plant juices.●Chem. formula: (CH3)3N+—CH2CO2−.
2. [ count noun] —
[Chemistry] any zwitterionic compound of the type represented by betaine.
– origin mid 19th cent.: formed irregularly from Latin beta ‘beet’ (because originally isolated from sugar beet) + -ine4.