noun
cartoon-character costume; mascot costume; kigurumi
A full-body costume that completely covers the wearer, often representing an animal, cartoon character, or mascot. The term is widely recognized in Japanese pop culture and is sometimes borrowed into English as 'kigurumi'.
遊園地で着ぐるみのクマと写真を撮った。
I took a picture with a person in a bear costume at the amusement park.
彼女はイベントで着ぐるみを着て踊った。
She danced in a kigurumi at the event.
Cosplay generally refers to dressing up as a specific character, often with detailed makeup and accessories, while 着ぐるみ specifically means a full-body costume that covers the face and body completely, typically of a mascot or animal.
仮装 is a broader term for dressing up in disguise or costume, not necessarily a full-body mascot-style outfit.
Compound of 着 (ki, 'wearing') and 包み (kurumi, 'wrapping'), literally 'wearing a wrapping'. The kanji 包み is often replaced with kana ぐるみ in modern usage.