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speaking by proxy; speaking for (someone else); acting as spokesman (for); representing (the views, feelings, etc. of)
payment by proxy; compensation by proxy; paying on behalf (of)
acting for (someone else); carrying out (on someone's behalf)
弁護士が被告人の立場を代弁した。
The lawyer spoke on behalf of the defendant.
彼女は社会的な弱者の声を代弁し続けている。
She continues to speak on behalf of the socially weak.
私の気持ちを代弁してくれてありがとう。
Thank you for speaking on my behalf.