「Tree with safety, peace and rest」or「tree with deliberately out-of-reach female」as EUCALYPTUS, a tree notable for its property of absorbing large quantities of fluids via the root structure (its feet), and for the antiseptic quality of extracted oils. Also called a 'fever tree': when planted in swampy areas, the roots dry the soil and eliminate breeding areas of mosquitoes, malaria carriers.
　Observe koalas that eat eucalyptus:「Koalas typically inhabit open eucalypt woodlands, and the leaves of these trees make up most of their diet. Because this eucalypt diet has limited nutritional and caloric content, koalas are largely sedentary and sleep for up to 20 hours a day.」
　　[　https://en.wikipedia.org/wiki/Koala 2013-10-13　]　
　「The oils may be roughly divided into three classes of commercial importance: (1) the medicinal oils, which contain substantial amounts of eucalyptol (also known as cineol). (2) the industrial oils, containing terpenes, which are used for flotation purposes in mining operations. (3) the aromatic oils, such as E. citriodora, which are characterized by their aroma. …It is also called the Fever Tree, being largely cultivated in unhealthy, low-lying or swampy districts for its antiseptic qualities.」
　　[　https://www.botanical.com/botanical/mgmh/e/eucaly14.html 2015-02-03　]　
　「Do Koalas get 'drugged out' on eucalyptus leaves? No. There is a common misconception that Koalas get 'drugged out' or 'high' on eucalyptus leaves and that's why they sleep a lot. This myth possibly arose as a way of explaining why Koalas sleep for up to 22 hours a day. They need more sleep than most animals because eucalyptus leaves contain toxins and are very low in nutrition and high in fibrous matter so they take a large amount of energy to digest. Sleeping for long periods is a strategy for conserving energy. Koalas and gliders are the only mammals which can tolerate the toxins in gumleaves but fortunately they don't make them 'high' or 'drugged out.'」
　　[　https://www.savethekoala.com/about-koalas/frequently-asked-questions/ 2015-02-03　]　So, take note that the「simpleton, coffin, encased death, numb with safe, security, peaceful, restful, ease, contentment, in good health, cute and safe in tree」elements were in fact erroneous, but apparently true nonetheless.

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: Eucalyptus globulus
Unihan extended: eucalyptus