ドウ 
() public chamber () hall
           
どう (n,n-suf,n-pref) (1) temple, shrine, hall, (2) prefix to building meaning "magnificent"
どうどう (adj-t,adv-to) (1) magnificent, grand, impressive, dignified, majestic, imposing, stately, (2) fair, square, open, (adv-to) (3) grandly, boldly, confidently, (4) fairly, squarely, (5) unreservedly, without apology, without hesitation

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Etymologies: 中文字譜 : 説文解字