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life

(Encyclopedia)life, although there is no universal agreement as to a definition of life, its biological manifestations are generally considered to be organization, metabolism, growth, irritability, adaptation, and ...

half-life

(Encyclopedia)half-life, measure of the average lifetime of a radioactive substance (see radioactivity) or an unstable subatomic particle. One half-life is the time required for one half of any given quantity of th...

life insurance

(Encyclopedia)life insurance: see insurance.

life preserver

(Encyclopedia)life preserver, a personal flotation device (PFD) intended to keep the wearer afloat, particularly in case of shipwreck. A Type I PFD will keep even unconscious people afloat in a face–up position; ...

still life

(Encyclopedia)still life, a pictorial representation of inanimate objects. The term derives from the 17th-century Dutch still-leven, meaning a motionless natural object or objects. In East Asia still-life subj...

life support system

(Encyclopedia)life support system: see artificial life support; Life Support for Human Spaceflight under space science. ...

artificial life support

(Encyclopedia)artificial life support, systems that use medical technology to aid, support, or replace a vital function of the body that has been seriously damaged. Such techniques include artificial pacemakers, in...

Census of Marine Life

(Encyclopedia)Census of Marine Life, an international program (2001–2010) to assess and explain the diversity, distribution, and abundance of living organisms in the oceans. A project involving more than 2,700 sc...