Dictionary
bar•rel•head
Pronunciation: (bar'ul-hed"), [key]—
n.
1. either of the round, flat sections that form the top and bottom of a barrel.
2. on the barrelhead, in advance or on demand:
They won't deliver the merchandise unless we pay cash on the barrelhead. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.