Boston Fern The most common indoor fern, Boston ferns are long-lived plants that can reach more than 5 feet tall and wide at maturity (though indoors they rarely reach that size). Fern breeders have released a large number of varieties -- from selections with golden fronds to fantastically frilled fronds.
Wiktionary(0.00 / 0 votes)Rate this definition: 1  green room(Noun) (entertainment) In a television studio, theatre or concert hall, the room where performers await their entrance. 2  green room(Noun) The inside of a tube (ie. of a wave making a tube).
Cleanroom Related Definitions. As Built: A functioning room with no furniture, process equipment, or personnel. Normally found only on new rooms. Very easy to pass. At Rest: Fully operational room with furniture, process and support equipment in place but not operating. The most common tested condition, also easy to pass, because no particles are being generated within the room. Ceiling Grid: Type or style of prefabricated ceiling system used in a cleanroom.