'alphabetically' originates from 'alphabetical', which is derived from the Greek word 'alphabētikos', where 'alpha' and 'beta' are the first two letters of the Greek alphabet.

'alphabētikos' transformed into the Medieval Latin word 'alphabeticus', and eventually became the modern English word 'alphabetical', with 'alphabetically' as its adverbial form.

Initially, it meant 'pertaining to the alphabet', but over time it evolved into its current meaning of 'in the order of the alphabet'.