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large; big; great; major; important; serious; heavy; loud
older; senior
final; ultimate
rough; broad; general
「大」 has other readings with different meanings.
大きな声で話してもらえますか。
Could I get you to speak in a louder voice?
この大きさでいいと思いますよ。
I think this size is good.
彼は大したことをやってのけた。
He accomplished something great.