The name for a complex individual that consists of organ systems is an organism.

Here's a breakdown:

* Organ: A structure made up of different tissues that work together to perform a specific function (e.g., heart, stomach, lungs).

* Organ System: A group of organs that work together to carry out a major bodily function (e.g., digestive system, respiratory system, circulatory system).

* Organism: A complete living being made up of multiple organ systems that work together to sustain life.

So, a human being, a tree, a dog, a bacterium, etc. are all examples of organisms.