A non-scientific condition typified by the presence of a big (even gigantic) head. May also be accompanied by slight retardation or the presence of retard strength.
I feel so sorry for Mary, with John's advanced macrocranialism, their kids have ginormous heads. There must have been some stretching down in the vag from those big heads passing through.
by Big Tilly September 15, 2006
Available Domains :D