A large bus that carries many passengers, or something that covers many different things in one collection.
From Latin 'omnibus' (for all, dative plural of 'omnis' meaning all). First applied to a type of carriage in Paris around 1828, then to buses. The Latin dative was chosen because the vehicle was 'for all' people.
The word 'omnibus' gave us the modern term 'bus'—it's literally the last two syllables being shortened and repurposed. This happened so often that Latin 'omnibus' vehicles became our everyday word for public transport.
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