bekpi -bek- experimental gismu

x1 is the 'back', dorsum of body x2

Opposite of ventral part of the body. Not necessarily should be a posterior part of the body. Determined by bilateral symmetry of the body. See also vente, trixe, cutne.

In notes:

bekybo'u
x1 is a vertebra / backbone of x2
dzibekslu
x1 is the lats (lower back muscles) of x2
galbekslu
x1 is the traps (upper back muscles) of x2
vente
x1 is the ventral part of body x2
verteba
x1 is a vertebra of body or body-part x2