The most popular term for the device invented by John C. Lilly in 1954 is floatation tank or float tank. The float tank solutions guide mentions a host of other terms:
But the most popular term is float tank and the most popular term for usage of the float tank is floating.
Floating is isolation from gravity
To be sure, effortless isolation from gravity is the hallmark of near death experiences, OBEs, etc. And floating might be the most impactful feature of the float tank. But the tank was intended to isolate you from all earthly senses, not just gravity.
Bringing sanskrit to the rescue. the float tank is more accurately termed a “pratyahara tank”, where pratyahara is a yogic term for “withdrawal of the senses”. In raja or ashtanga (8-limbed) yoga, pratyahara is the 5th step on 8 steps to self-realization. Lee and Glenn Perry’s company is named “Samadhi” which is the 8th and final stage. Whether getting into a tank and experiencing pratyahara is adequate to achieve samadhi is a fascinating topic of debate.
Filtration is one of many water sanitization processes.
Insuring the hygiene of the water used in a tank is most popularly referred to as floatation. E.g. from the float tank solutions guide on float tanks we see them refer to the entire treatment process a filtration:
More references to the entire water treatment process as “filtration” can be seen in this flaming thread on reddit – filtration, sterilization, sanitation: should we be more precise? : r/FloatTank (reddit.com)
The Samadhi Tank co refers to the process as filtration as well:
But clearly:
- filtration is removal of something
- sterilization is killing something harmful
- sanitation is making something safe and hygienic
So: sanitation includes sterilization and filtration.
A list of sterilization processes is a useful related study topic.
A rectangle is not a square…
So we have at least 2 cases in the world of REST where the square is named with the rectangle. I’m alright with that angle.