生物：兩種生物長期住在一起
這一支就是畫面本身。蜜蜂與花、地衣、腸道細菌都屬於這裡。學校課本、自然科報告最常出現。
noun · B2
In biology, a close relationship between two different kinds of living thing that live together for a long time, usually one in which each one helps the other survive.
共生
核心畫面
One way to picture symbiosis: two things that are not the same kind end up sharing one life. A fungus and an alga grow into a single crust on a rock and nobody can say where one stops. A bee and a flower meet again every summer, and each has become part of how the other keeps going. Take one side away and the other changes. The word travels from that picture to shops that feed each other customers, and to a street where tin roofs and glass towers stand side by side.
symbiosis 可以想成一幅畫面：兩個本來不同類的東西，過起了同一種生活。真菌跟藻類一起長成石頭上的一片地衣，分…更多收起
symbiosis 可以想成一幅畫面：兩個本來不同類的東西，過起了同一種生活。真菌跟藻類一起長成石頭上的一片地衣，分不出誰是誰。蜜蜂和花年年見面，久了各自都變成對方活下去的一部分。抽掉任何一邊，另一邊都會變樣。這幅畫面後來被借去講互相帶客的店家，也被借去講鐵皮屋跟玻璃大樓並排的一條老街。From the word’s history
The supplied source records the word as coming from Ancient Greek sumbíōsis, living together, and analyses it on the surface as sym- plus -biosis. That is the picture itself: the two parts of the word already say together and life.
來源資料記的是：這個字來自古希臘文 συμβίωσις（sumbíōsis），意思就是「一起生活」，拆開看是 sym-（一起）＋ -biosis（生活）。所以上面那幅畫面其實就寫在字裡面——「一起」和「生活」這兩塊，本來就是它的組成。
Wiktionary entry supplied in the evidence packet (source_ref kaikki:3f6f69a190036ae4:776671139)
Three branches
人與組織：互相需要、誰也少不了誰
把生物那幅畫面搬到人身上。兩個單位各出一點、各得一點，關係夠對等，抽掉一邊另一邊就垮。這是報導和分析文章裡最常見的用法，語氣正式。
noun · C1
A close working relationship between two people, groups, or organizations in which each side needs the other and each gets something from it, so neither would do as well alone.
互相依存的關係
並存：兩種很不一樣的東西同時在場
這一支把畫面裡的「互相得利」拿掉，只留下「一起」。剩下的重點是：兩種不同、甚至相反的東西，同時待在同一個地方，而且彼此都被影響。用法偏文學、偏描述。
noun · C1
The state of two different — sometimes opposite — kinds of people or things existing together in the same place at the same time, each one affecting the other.
並存共處