behalf

noun

be·​half bi-ˈhaf 

-ˈhäf,

bē-

: interest, benefit

also : support, defense

argued in his behalf

On Behalf of vs. in Behalf of: Usage Guide

A body of opinion favors in with the "interest, benefit" sense of behalf and on with the "support, defense" sense. This distinction has been observed by some writers but overall has never had a sound basis in actual usage. In current British use, on behalf (of) has replaced in behalf (of); both are still used in American English, but the distinction is frequently not observed.

Phrases

on behalf of or in behalf of

: in the interest of

also : as a representative of

I wrote the letter on behalf of my client.

Examples of behalf in a Sentence

Recent Examples on the Web

One of them is David McIntosh, president of the Club for Growth, a group that ostensibly intervenes in GOP primaries on behalf of candidates who support smaller government. —David M. Drucker, Twin Cities, 19 Oct. 2025

In court filings, the Justice Department, which argues these cases on behalf of the government, said that the re-detention is legal because the agency has once again requested new travel documents from Ukraine. —Ximena Bustillo, NPR, 19 Oct. 2025

The lawsuit is filed on behalf of Brockman’s mother, listed in the lawsuit as Tracy Brock. —Kendrick Calfee, Kansas City Star, 19 Oct. 2025

At her sentencing hearing, the defense called Lorincz’s sister and an expert in psychological trauma to testify on her behalf, CNN reported. —Lynsey Eidell, PEOPLE, 18 Oct. 2025

Word History

Etymology

Middle English, from by + half half, side

First Known Use

14th century, in the meaning defined above

Phrases Containing behalf

• in behalf of someone
• in someone's behalf
• on behalf of someone
• on someone's behalf

Rhymes for behalf

• carafe
• digraph
• distaff
• falstaff
• giraffe
• subgraph
• autograph
• biograph
• cenotaph
• chronograph
• epigraph
• epitaph

Kids Definition

behalf

noun

be·​half bi-ˈhaf 

-ˈhȧf

: useful aid : support

spoke in my behalf