'amobarbital' originates from 'barbituric acid', specifically the word 'barbital', where 'barb-' referred to 'barbituric acid' and '-ital' was a common suffix for barbiturates.

'barbital' changed from 'barbituric acid' word 'barbital' and eventually became the modern English word 'amobarbital'.

Initially, it meant 'a derivative of barbituric acid used as a sedative', and this meaning has largely remained the same in modern usage.