be ‧ half S3 W3 AC /bɪˈhɑːf $ bɪˈhæf/ BrE AmE noun
[ Date: 1300-1400 ; Origin: by half 'on (someone's) side' ]
on behalf of somebody ( also in behalf of somebody American English )
a) instead of someone, or as their representative:
She asked the doctor to speak to her parents on her behalf.
On behalf of everyone here, may I wish you a very happy retirement.
b) because of or for someone:
Oh, don’t go to any trouble on my behalf.