vital

Vital is an adjective used to describe something indispensable or essential. It can also pertain to life itself, as in vital organs and vital functions. In general usage, the term signals great importance or necessity; for example, timely medical care is vital to patient survival, and securing funding is a vital step in a project.

The word derives from Latin vitalis, meaning "of life," from vita "life." English usage has expanded to many compounds, such as vital signs, vital capacity, and vital statistics, all emphasizing either life processes or essential information.

In medicine and physiology, vital signs are measurements that reflect basic body functions, including heart rate, blood pressure, respiratory rate, and temperature. Vital capacity is the maximum amount of air a person can exhale after a full inhalation. Vital statistics refer to demographic data on births, deaths, marriages, and migrations; vital records are the official documents that record these events.

Historically, vitalism was a philosophical doctrine that posited a life force beyond physical and chemical explanations. It faded as modern biology offered mechanistic accounts of life. The term vital also appears in related forms such as vitality, denoting liveliness, and vitalize, meaning to make something more vigorous.