multicellular
adjective
mul·ti·cel·lu·lar ˌməl-tē-ˈsel-yə-lər 
-ˌtī-
: having, made up of, or involving more than one and usually many cells especially of living matter
It is probable that with a few exceptions all the cells in a multicellular organism have the same genetic information encoded in the chains of nucleotide bases that make up their DNA.
James E. Darnell, Jr.
James E. Darnell, Jr.A biofilm is a community of bacteria that use intercellular signaling to establish complex multicellular structures by coordinating gene expression and phenotypic changes. J. Christopher Post et al.
J. Christopher Post et al. multicellularity
ˌməl-tē-ˌsel-yə-ˈler-ə-tē
noun -ˌtī-
-ˈla-rə-
When is an organism multicellular? A generic answer … is that multicellularity results when two or more neighboring cells adhere, interact, and physiologically communicate. Karl J. Niklas
Karl J. Niklas 
Did you know?
Multicellular organisms are distinguished from the very primitive single-celled organisms—bacteria, algae, amoebas, etc. Even sponges, simple as they are, have specialized cell types such as digestive cells. In complex multicellular organisms, only the surface cells can exchange substances with the external environment, so the organisms have developed transport systems such as the circulatory system, in which the blood brings gases and nutrients to the cells and removes waste products from them.
Word History
First Known Use
1852, in the meaning defined above
Medical Definition
multicellular
adjective
mul·ti·cel·lu·lar -ˈsel-yə-lər
: having or consisting of many cells