Aminobutyric acid
The company name "GABA" is an acronym for "girls, be ambitious; boys, be audacious!". According to a speech given by co-founder Hideki Yoshino, he chose this name because he had a keen interest in physical fitness, and named it after Gamma-Aminobutyric acid, an amino acid used by bodybuilders. Many other large Japanese English conversation schools at the time also had four letter names, such as Nova, GEOS, and Aeon, and giving the school a four letter name would help it fit in.