Mold is primarily a multicellular organism, consisting of networks of filaments called hyphae that form a structure known as mycelium. While individual cells within the mold can function independently, they typically work together to form the larger multicellular structure. However, some molds can also exist in a unicellular form, such as yeasts, which are a type of fungus.
It is multi celled.
Single
Single-cell
Bacteria are single-celled organisms
multi celled
They are multi-cellular.
multi celled of coures
multi celled
Onions are multicellular, but this term refers to the entire organism - you cannot call a single onion cell a "multi cell".
a slime mold
A fungi is a multi-cell but can be a single cell
Turtles are definitely multi-celled. Single cell organisms are microorganisms such as bacteria and the protozoans.