An onomatopoeic word meaning to be dejected or dispirited; describes when someone's spirits fall and their posture/expression droops.
試合に負けて彼はシュンと部屋へ戻っていった。
He lost the match and went back to his room looking dejected.
先生に注意されて子どもはシュンと肩を落とした。
When the teacher scolded him, the child slumped his shoulders dejectedly.
犬は叱られるとしっぽを下げてシュンとした表情になる。
When the dog is scolded, it tucks its tail and looks dejected.