'Bachelor's' originates from English, specifically the possessive form of the noun 'bachelor', which ultimately comes from Old French 'bacheler' and Medieval Latin 'baccalarius', where 'baccalarius' meant 'young man; junior member or tenant'.

'Bachelor's' formed in English as 'bachelor' + possessive '’s'. The noun 'bachelor' entered Middle English from Old French 'bacheler' and was influenced in academic contexts by Medieval Latin 'baccalaureus', which contributed to the university sense.

Initially, 'bachelor' meant 'young knight; novice' and later 'unmarried man'. In university contexts it came to mean 'junior member' and then 'holder of the first university degree'; 'Bachelor's' as a standalone noun arose by ellipsis of 'bachelor's degree'.