noun, masculine/ɔs.to/plural: hostos
hospital; lodging; abode
“Il a été transporté d’urgence à l’hosto.” — He was rushed to (the) hospital.
Borrowed from a regional language of France, ultimately from Latin hospitālis. Doublet of hôtel. First documented as soldiers' slang in 1915. The army provided an environment ripe for this sort of borrowing, as it had brought together conscripts from across the country. The spelling with ⟨eau⟩ is original. Modern speakers prefer ⟨o⟩ as the word has effectively been 'adopted' as the o-clipping of hôpital.