'On behalf of' definitions:

Definition of 'On behalf of'

From: GCIDE

Behalf \Be*half"\, n. [OE. on-behalve in the name of, bihalven by the side of, fr. AS. healf half, also side, part: akin to G. halb half, halber on account of. See Be-, and Half, n.] Advantage; favor; stead; benefit; interest; profit; support; defense; vindication. [1913 Webster]
In behalf of his mistress's beauty. --Sir P. Sidney. [1913 Webster]
Against whom he had contracted some prejudice in behalf of his nation. --Clarendon. [1913 Webster]
In behalf of, in the interest of.
On behalf of, on account of; on the part of. [1913 Webster]