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leaf  (lēf)
Share:
n. pl. leaves (lēvz)
1. A usually green, flattened, lateral structure attached to a stem and functioning as a principal organ of photosynthesis and transpiration in most plants.
2. A leaflike organ or structure.
3.
a. Leaves considered as a group; foliage.
b. The state or time of having or showing leaves: trees in full leaf.
4. The leaves of a plant used or processed for a specific purpose: large supplies of tobacco leaf.
5. Any of the sheets of paper bound in a book, each side of which constitutes a page.
6.
a. A very thin sheet of material, especially metal.
b. Such leaves considered as a group: covered in gold leaf.
7.
a. A hinged or removable section for a table top.
b. A hinged or otherwise movable section of a folding door, shutter, or gate.
c. A section of drawbridge that moves upward or to the side.
8. One of several metal strips forming a leaf spring.
v.leafed, leaf·ing, leafs
v.intr.
1. To produce leaves; put forth foliage: trees just beginning to leaf.
2. To turn pages, as in searching or browsing: leafed through the catalog.
v. tr.
To turn through the pages of.
Phrasal Verb:
leaf out
To put forth leaves, especially after a period of dormancy: the period in the spring when trees begin to leaf out.
Idioms:
take a leaf from (someone)
To use (someone) as an example.
take a leaf from (or out of) (someone's) book
To use (someone) as an example.

[Middle English, from Old English lēaf.]
(click for a larger image)
(click for a larger image)
leaf
top: anatomy of a leaf
bottom: a double-leaf bascule drawbridge

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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