榜
ボウ, ホウ, かじ, たてふだ, ふだ

rudder, oar, name plate

JLPT0 G13 S0 F5000

As per 旁# (spread to/be on both sides) + 木 tree/wood → placard/*nameplate* with writing on both sides → *display*. *Strike* (with a *whip*) is a borrowed meaning.

[Full Kanji Etymology List]