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

More importantly, this represents a shift from AI tools to AI agents, systems that work autonomously on behalf of users rather than merely assisting them. —Douglas B. Laney, Forbes.com, 4 Aug. 2025

David Smith, an attorney arguing on behalf of Southern Legacy of Life, said allowing the measure to be enforced would insert uncertainty into organ donations both in the state and nationally. —Arkansas Online, 4 Aug. 2025

According to The Sun, the initial allegations of cocaine use came via a legal submission to the BBC several months back by law firm Russells on behalf of the former celebrity contestant Wynne Evans. —Max Goldbart, Deadline, 4 Aug. 2025

Figma declined to provide a comment on behalf of Wallace, and Fortune was unable to reach him directly. —Allie Garfinkle, Fortune, 2 Aug. 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