「It was the summer of 1724, and two groups of Japanese villages were arguing over a sewage issue in Osaka. The dispute was about waste removal, but not quite in the way one would imagine. The villages weren't arguing about whose job it was to dispose of the filth, but rather about who had the rights to collect it, keep it, and use it. Notably, the village residents didn't consider the substance filth. They used a special term, NIGHT SOIL, to describe the product they were after. And they were in dire need of it.」
　　[　https://daily.jstor.org/a-history-of-human-waste-as-fertilizer/　]　
　Possibly elements are「up is horizon」as it refers to being underground, EARTH, GROUND, SOIL, CLAY. Per the archeologists, the first housing projects as cave people were leaving their cavern dwellings were pits or holes dug into the ground or the side of a slope, later lined with stones or bricks and mud or mortar.
　「The word MANURE itself has its origins in nothing at all to do with excrement: the roots are Latin words for 'hand' and 'work,' and the compound of the two originally meant 'to cultivate' or 'to hold property'」 [that is, a LAND owner, as it were] who engaged in spreading fecal fertilizer to enrich the soil.
　　[　https://www.wired.com/story/history-poop-is-really-history-technology/ 2022-08-23　]　
　From time immemorial before the beginning, humans have collected feces and used it as fertilizer. Still today, researchers are working on finding solutions for problems facing humanity. It is not only feces that are an excellent fertilizer. Urine works, too! "Innovative system turns human waste into sustainable fertilizer: Stanford researchers have developed a prototype that harnesses urine to generate valuable fertilizer, offering solutions for sanitation and energy in resource-limited regions."
　　[　https://news.stanford.edu/stories/2025/08/prototype-urine-human-waste-fertilizer-sustainable-energy-research/ 2025-08-21　]　
　Best practices dictated that a person go up and exit the pit hole while defecating at night, creating the notion of NIGHT SOIL, or FECES, MANURE, FERTILIZER, STOOL, SHIT, the assigned meaning of this glyph (see 坺) that is also prevalent in Chinese astrological soothsaying (四柱推命) as various types of an「emergence from flesh seam.」Also referring to a proclivity of some folks for penetration into night soil, this same shape as an element sometimes represents「penis」(士) in modern fonts, suggesting a merging of the elements「reciprocating rod motions inside flesh seam」not unlike 'rod among, within an orifice' (中), noting that when with one's buddies only and no females, the only flesh seams available will constitute NIGHT SOIL, FECES, STOOL.
　SOIL CONDITIONS. In English also, 'continent' can refer to (very) large clumps of soil sticking together forming one piece, such as Pangaea, but furthermore means「able to control urination and defecation. Exercising self-restraint, especially from sexual activity. Chaste」by not accessing the orifice normally attributed to conception. Conversely, 'incontinent' refers to the opposite soil condition of spurting slurry, uncontrollable urges, fluids mixed with feces that cannot hold together as one clump.
　 　[　https://www.thefreedictionary.com/continent 2014-03-03　]　
　As「up is horizon」glyph may be depicting a view after the ground has been penetrated while a person is inside his scorpion-like burrow, and not while standing above at ground level, while still living in dug out holes and pits as do scorpions (you would need to move「up」to get out):「The deadliest earthquake in recorded history rattled the Shensi (Shaanxi) province of China on Jan. 23, 1556, and killed an estimated 830,000 people. The death toll was particularly high among peasants who lived in artificial caves that were dug into soft rock and collapsed during the quake.」
　　[　https://www.history.com/this-day-in-history/deadliest-earthquake-in-history-rocks-china 2023-05-14　]　
　The death toll becomes even more remarkable when you consider the estimated total worldwide population in 1556 prior to that single seismic event in one locale.
　…Seems like there were still an awful lot of pit hole homes in Asia only 500 years ago, and still today:「In north China, especially on the Loess Plateau, caves called yaodongs dug into hillsides have been the traditional dwellings from early times. The advantage of a yaodong over an ordinary house is that it needs little heating in winter and no cooling at all in summer. An estimated 40 million people in northern China live in a yaodong. Many people live in semi-recessed dugout houses in north-western China where hot summer and cold winters prevail.」
　　[　https://en.wikipedia.org/wiki/Pit_house 2012-07-02　]　
　In ancient Japan:「The Early Jōmon is the first stage…of Japanese pre-history…[and] ranged from 10,000 to 300 BC…. This period saw a rise in complexity in the design of pit houses, the most commonly used method of housing at the time.」
　　[　https://en.wikipedia.org/wiki/J%C5%8Dmon_period 2012-07-02　]　

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: earth; dust; clay; local; indigenous; crude opium; unsophisticated; one of the eight ancient musical instruments 八音; Tu (ethnic group)
Japanese: earth, soil, dirt, clay, mud, the earth, the ground, the land, low-quality torinoko-gami, refraining from construction in the direction of the god of the earth, Saturday, Turkey, sandbag, playing with dirt, gardening, farming, keeping in good condition, to die, to become earth, dust, cloud of dust
Unihan extended: soil, earth; items made of earth
EDRDG: soil; earth; ground; Turkey

Used within names (nanori)
つ　･　つく　･　は　･　ひじ