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honest; respectable; decent
respectable occupation (i.e. not yakuza, prostitute, etc.)
person in a respectable occupation
出所後、彼は堅気になった。
After his release, he went straight.
我が家は代々堅気な商売だ。
Our family has run a respectable business for generations.
娘は堅気の男性としか結婚しないと言い張った。
My daughter insisted she would only marry a respectable man.