Ookini
Osaka's own word for thank you, used in place of the standard Japanese arigatou. You'll hear it constantly from shopkeepers and market stall staff, and it's one of the clearest, most immediate signals that you've crossed from standard Japanese territory into Osaka-ben.
Maido
A catch-all greeting used heavily by shopkeepers and restaurant staff, roughly meaning something between 'welcome' and 'thanks for coming by again' — used whether it's your first visit or your fiftieth.
Honma
Osaka-ben's version of hontou, meaning 'really' or 'truly' — often used as a standalone reaction, similar to saying 'seriously?' or 'for real?' in English.
Akan
Means roughly 'no good' or 'can't do that' — a blunt, common way of saying something isn't allowed or isn't going to work, used far more casually and frequently than its standard Japanese equivalents.
Chau chau
A doubled-up way of saying 'no, that's wrong' — chau alone already means 'different' or 'no,' and repeating it is a distinctly Osaka rhythmic habit that shows up constantly in the city's manzai comedy.