Not divided into segments; noting the egg which has not undergone cleavage, or the embryo or parts of the embryo which show no metameric arrangement of their parts.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adj. having a body that is not divided into segments
Word Usage
"Slight differences in rates or slight differences in interaction parameters between molecules and cells can change an organism that is a continuous unsegmented form to an organism that's segmented."