'bachelorlike' is formed in modern English by combining the noun 'bachelor' with the adjective-forming suffix '-like' (from Old English 'līc' meaning 'having the form of').

'bachelor' entered English via Old French 'bacheler' (Medieval Latin 'baccalarius' / 'baccalaureus'), originally referring to a young man or novice (and later a young knight), then shifting to mean an unmarried man; the productive suffix '-like' derives from Old English 'līc' and by compounding produced 'bachelorlike' as an adjective.

Originally, 'bachelor' meant 'young man' or 'young warrior' and later 'unmarried man'; combined with '-like' it evolved to mean 'having the qualities or appearance of an unmarried man' (the modern sense of 'resembling a bachelor').