謹
キン, つつし.む

discreet, reverently, humbly

JLPT1 G7 S17 F2068

As per ?# as described in 漢 (minute) + 言 words → pay minute attention to one's words → circumspection → *consideration*; *caution*; *restraint*; *humility* → polite term of *respect* for another.

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