The process by which a plant loses water: water travels up from the roots, through the stem, and escapes as vapour through tiny holes on the surface of the leaves. It is basically a plant sweating and breathing out water at the same time — and it is not waste.

The process by which a plant loses water指的是植物失去水分的過程：water travels up from the roots水從根部往上走, through the stem通過莖部, and escapes as vapour through tiny holes on the surface of the leaves再從葉片表面的小孔以水蒸氣的形式散發出去。It is basically a plant sweating and breathing out water at the same time這基本上就是植物同時在流汗和呼出水氣 — and it is not waste而且這不是浪費。

That upward pull of escaping water is what drags more water and minerals up from the soil, which is how a tall tree gets water to its top leaves with no pump.

That upward pull of escaping water那股往上散失水分的拉力 is what drags more water and minerals up from the soil正是把更多水分和礦物質從土壤裡拉上來的動力, which is how a tall tree gets water to its top leaves with no pump這就是一棵高大的樹沒有幫浦也能把水送到最頂端葉子的方法。

This is a biology word, and for most students it arrives in a science class, often in the same lesson as photosynthesis and respiration. The three sit together and are easy to mix up: photosynthesis makes food using light, respiration releases energy from food, transpiration moves and loses water.

This is a biology word這是一個生物學的字, and for most students it arrives in a science class而對大多數學生來說，它是在自然課裡學到的, often in the same lesson as photosynthesis and respiration常常和光合作用、呼吸作用一起教。The three sit together and are easy to mix up這三個字放在一起很容易搞混：photosynthesis makes food using light光合作用是利用光製造食物, respiration releases energy from food呼吸作用是從食物釋放能量, transpiration moves and loses water蒸散作用則是搬運並失去水分。

Related phrases you will meet: 'transpiration rate', 'the transpiration stream', and in geography 'evapotranspiration' (water lost from soil and plants together). Outside science the word is rare. There is an older, more literary use meaning something becoming known or an event happening — but that belongs to the verb 'transpire', and if you say 'transpiration' in normal conversation, people will assume you are talking about plants.

Related phrases you will meet你會遇到的相關用語有：'transpiration rate'蒸散速率, 'the transpiration stream'蒸散流, and in geography 'evapotranspiration'還有地理科的蒸發散 (water lost from soil and plants together)指的是土壤和植物一起散失的水分。Outside science科學課以外, the word is rare這個字很少見。There is an older, more literary use還有一個較老、較文學性的用法 meaning something becoming known or an event happening意思是某件事變得眾所皆知或發生了 — but that belongs to the verb 'transpire'不過那是動詞'transpire'的用法, and if you say 'transpiration' in normal conversation如果你在平常對話裡說'transpiration', people will assume you are talking about plants大家會以為你在講植物。