Definition of breech:
(n) :
the lower part of the body behind; the buttocks; a reference to a view of or visual aspect of the buttocks or rear lower body below the waist, from which meaning is derived the term breech birth, the word in this case apparently referring to the obvious cleavage between the buttocks
(v) :
with the hips coming out before the head
(adj) :
born, or having been born, breech