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central figure; pillar (e.g. of the nation); mainstay; chief support; leader
chief; boss; leader; head
master carpenter
beams and ridge supports of a roof
「棟梁」 has another reading with different meanings.
棟梁が現場で指揮を執る。
The master builder directs the work on site.
彼は国の棟梁として皆に慕われた。
He was revered by all as the pillar of the nation.
弟子は将来、立派な棟梁になることを夢見ている。
The apprentice dreams of becoming a great master builder someday.