Outside the living body and/or in an artificial environment.

In a test tube.

in an artificial environment. For example many cancer research experiments are in vitro (in the test tube), using cell cultures (cells grown in the lab); either from established cell lines or from material collected at biopsy/surgery. See also: In-Vivo

inN-VEE-troh) To be reared or raised on an artificial or non-living host or development diet.

In the artificial living state environment, for example within a glass as an experiment.

Within an artificial medium like a test tube or culture dish, outside and separate from an entire living organism. Example: studies done on cells in vitro means test tube cultures of cells are grown and studied for one or more of their properties.