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corner; section; point; part
one horn
pillar (of a group, system, etc.); member (of an organization, etc.)
first corner
narwhal (Monodon monoceros)
「一角」 has another reading with different meanings.
部屋の一角を飾った。
I decorated a corner of the room.
街の一角に店を開いた。
I opened a shop in a corner of the town.
その事件は社会の一角を揺るがした。
That incident shook a part of society.