Answer:
Multicellular means that the organism is composed of many cells.
Explanation:
Multicellular means that the organism is very complex composed of many cells. These cells are visible like human beings, plants and animals. All of them begin their life with a single cell and slowly the cells multiple to become multicellular. Literary, the meaning of multi is 'many' and cellular is obtained from the Latin word 'cellularis' which means ' of little cells'.
Multicellular organisms have multiple cells which have a particular function to perform. Many cells fuse to form tissues, tissues merge to form organs and organs unite together to form an organ system. Each organ system has specialised functions which help in the proper functioning and survival of multicellular organisms.