behalf

The interest, benefit, or wellbeing of someone or something.

• She appeared on behalf of the U.N. Secretary General at a conference held in behalf of the world's children.

One's role or rightful place; stead or authority.

• He was not only my Representative who died on my behalf; He was my Substitute who died in my very stead.
• Hillary Clinton hasn’t hit the campaign trail yet on behalf of Democrats running in 2018, but that isn’t stopping Republicans from using the former 2016 Democratic presidential nominee as a reliable campaign boogeyman.