Oyster is actually oysters

Oysters, also known as oysters, oysters (Cantonese region), oysters (southern Fujian region), also known as sea oysters, oyster yellow, oyster white, green oysters, oysters, oyster clams, oyster clams, ????????????????????????????????????, belonging to the mollusc phylum Bivalvia. On the biological point of view, these names are called in different regions, but say the same thing.

Is it the size of the one above?

Is oyster omelette the one that is fried and eaten?