an organism which develops from an embryo and consists of many cells.

That group of multicellular animals characterized by two layers of cells in the gastrula stage of development.

any animal of the subkingdom Metazoa; all animals except protozoans and sponges

Multicellular organism (e.g. worms). A protozoan is a unicellular organism.

multicellular organism with eukaryotic cells (those containing genetic material in the nucleus).

A multicellular organism.