Do you know what they call this?

I see this umbrella like thing a lot lately especially at weddings.I don't know what it's called but my instinct tells me it's not called umbrella.You know how Nigerians are.You call it umbrella and they look at you like you are local *yes we are that judgemental*.So all the event planners,wedding planners,party people,I ain't too shy to ask o.What do you call this and what is its essence at weddings?Thank you in advance.