The Collaborative International Dictionary
In behalf of
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.
In behalf of his mistress's beauty.
--Sir P.
Sidney.
Against whom he had contracted some prejudice in behalf
of his nation.
--Clarendon.
In behalf of, in the interest of.
On behalf of, on account of; on the part of.
Wiktionary
in behalf of
prep. (alternative form of on behalf of English)