扇
セン, おうぎ, おう, おおぎ

fan, folding fan

JLPT1 G7 S10 F1805

戸 here an abbreviated form# of 扁 (spread, but remain in contact) + 羽 feather/wing → folding *fan*, the slats of which spread but remain in contact when the fan is in use.

[Full Kanji Etymology List]