Macrobiotic refers to the macrobiota, a regions living organisms (or flora and fauna) large enough to be seen with the naked eye. However, macro- comes from the Greek "makros" meaning not only "large" but also "long". So macrobiotic can also be taken to mean "long life." Thus, the idea with a macrobiotic diet is that it is for a long life, that is that the diet will lengthen life.
MACROBIOTIC
Meaning of MACROBIOTIC in English
English dictionary of medicine. Английский словарь медицины. 2012