'mob-like' originates from English, formed by combining the noun 'mob' (shortened from the Latin phrase 'mobile vulgus' used in English political writing) and the adjectival suffix '-like' (from Old English 'līc'/'lic' meaning 'body, form; similar to').

'mob' originated from the Latin phrase 'mobile vulgus' ('mobile' + 'vulgus') and entered English usage in the 17th–18th centuries as 'mob' (shortened). The suffix '-like' comes from Old English 'līc' (later Middle English '-like'), which developed into the productive adjectival suffix '-like' in Modern English. These elements combined in Modern English to form the compound adjective 'mob-like'.

Initially, 'mobile vulgus' referred to a 'movable' or 'fickle crowd'; 'mob' later came to mean an unruly or potentially violent crowd. The compound 'mob-like' originally meant 'similar to a crowd' and has come to carry the connotation 'resembling a disorderly or violent crowd'.