Wakame, also known as miyeok (Korean) and sea mustard, is a type of edible brown algal seaweed (kelp). It is native to East Asia, and it is frequently used in Japanese and Korean cuisines. It has green leaves or fronds, and it is frequently sold dried, to be reconstituted with water when cooking.
Wakame is often used in soups and salads. In Korea, wakame is used to make miyeok-guk (미역국), a seaweed soup traditionally eaten on one's birthday.