出典:Wiktionary
出典:『Wiktionary』 (2026/05/17 09:14 UTC 版)
From 中期英語 leef, from 古期英語 lēaf, from Proto-West Germanic *laub, from Proto-Germanic *laubą (“leaf”), from Proto-Indo-European *lowbʰ-o-m, from *lewbʰ- (“to cut off”).
(Internet slang: Canadian): In reference to the maple leaf as national symbol.
leaf (countable and uncountable, plural leaves)
leaf (third-person singular simple present leafs, present participle leafing, simple past and past participle leafed)
From Proto-West Germanic *laub, from Proto-Germanic *laubą. Cognate with Old Saxon lōf, Old High German loub, Old Norse lauf, Gothic 𐌻𐌰𐌿𐍆𐍃 (laufs).
出典:Wikipedia
出典:『Wikipedia』 (2011/06/06 23:07 UTC 版)
In botany, a leaf is an above-ground plant organ specialized for the process of photosynthesis. Leaves are typically flat (laminar) and thin which evolved as a means to maximise the surface area directly exposed to light. Furthermore the internal organisation of leaves has evolved to maximise exposure of the photosynthetic organelles, the chloroplasts, to light and to increase the absorption of carbon dioxide, all of which assist photosynthesis. These adaptations are at the expense of water loss and most leaves have stomata which regulate carbon dioxide, oxygen and water vapour exchange with the atmosphere. The shape and structure of leaves varies considerably depending on climate, primarily due to the availability of light and potential for water loss due to temperature and humidity. Leaves are also the primary site, in most plants, where transpiration and guttation take place. Leaves can also store food and water, and are modified in some plants for these purposes. The concentration of photosynthesis in leaves makes them rich in protein, minerals and sugars. Because of their nutritional value leaves are prominent in the diet of many animals, including humans as leaf vegetables.
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a leaf
a leaf
葉の
a spotted leaf
a tomentose leaf
a laciniate leaf
a bamboo leaf
a burdock-leaf
dewdrop from a leaf
a willow leaf
a loose leaf
a pressed leaf
たね
a falcate leaf
the blade
落ち葉.
子葉.
a seminal leaf