YOSI is a slang derivative of the Tagalog word SIgarilYO (from Spanish, cigarrillo for cigarette), with its first and last syllables put together in reversed order.\r\n\r\ncigarrillo = sigarilyo = SI garil YO = SIYO = YOSI\n> Huy! Mag-yosi muna tayo...\n> "Hey! Let's have a cigarette first..."\n