'amidin' originates from the word 'amidine,' which is derived from the combination of 'amide' and the suffix '-ine,' indicating a chemical compound.

The term 'amidine' was coined in the late 19th century as chemists began to identify and categorize new functional groups in organic chemistry.

Initially, it referred to any compound containing the amidine group, and this meaning has remained consistent in modern usage.