Plural of bus: large vehicles designed to carry many passengers; or plural of buss, meaning kisses.
From Latin 'omnibus' (for all, dative plural of 'omnis'). The kiss meaning from Latin 'bussium' (a kiss). Homonyms that reached English through different routes.
The word 'omnibus' literally means 'for everyone'—hence a vehicle for the masses—but 'omnibus' also gave us 'omnibus bill' in politics, a single law covering many different topics, same root, same spirit of multiplicity.
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