Lifeform
A lifeform, organism, or life-energy force was a disctinct entity generally considered to exhibit signs of "life". 

Not all criteria for life are universally applicable in defining lifeforms, as organic, inorganic, artificial, and non-corporeal entities have all been considered lifeforms. (; ) 

In 2267, Spock noted that "life as we know it is universally based on some combination of carbon compounds, but what if life exists based on another element? For instance, silicon." This while theorizing what would eventually be determined to be the Mother Horta. ()

Later, when the Organians revealed their true form, the same year, Spock observed: "Fascinating. Pure energy. Pure thought. Totally incorporeal. Not life as we know it at all." ()

In 2269, Spock noted, in addition to the crew of the  and their Klingon guests that "[t]here appear to be more life-energy units on board than can be accounted for by the presence of [both crews]," something he considered to be "a considerable discrepancy", and in fact was the first indication of the non-corporeal Beta XII-A entity aboard the ship. ()

Most space-faring civilizations built devices to remotely detect and locate known lifeforms. Starship sensors and tricorders were the primary instruments used, as they could identify or localize blood type, heart rate, or metabolic setup. Typically, only organic lifeforms were detected. ()

According to Captain Jonathan Archer, over seventy percent of the organisms on Earth are bacteria. ()

Types 
Artificial lifeform
Biomimetic lifeform
Carbon-based lifeform
Animal
Bacterium 
Fungus
Plant
Protozoan
Cyborg
Dark matter lifeform
Metallic lifeform
Non-corporeal lifeform
Cloud creature
Photonic lifeform
Silicon-based lifeform
Solanogen-based lifeform
Spaceborne species
Sporocystian lifeform
Virus
Xenon-based lifeform

Starfleet lifeform classification 
 Classification R-3 lifeforms (Sheliak)
 Class-5 lifeforms (Vhnori)

 Order 480-G anthropoids (Taurus II natives)

See also 
 Anatomy
 Lifeform identification

External links 
 
 

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