What does the term 'extinct' signify?

The term 'extinct' signifies that a particular species or group of organisms no longer exists in any form. This means that all individuals of that species have died out and there are no remaining populations. It is a classification used primarily in biology and conservation to indicate a complete loss of a species, often due to factors like habitat destruction, climate change, or human activity. This concept is important in the study of biodiversity, as understanding extinction can help scientists and conservationists take steps to protect other endangered species and preserve ecosystems.