noun, often attributive \ˈlēf\

: one of the flat and typically green parts of a plant that grow from a stem or twig

: a sheet of paper in a book

: a part that can be added to or removed from a table to change the size of its top surface

plural leaves \ˈlēvz\ also leafs \ˈlēfs\

Full Definition of LEAF

a (1) :  a lateral outgrowth from a plant stem that is typically a flattened expanded variably shaped greenish organ, constitutes a unit of the foliage, and functions primarily in food manufacture by photosynthesis (2) :  a modified leaf (as a bract or sepal) primarily engaged in functions other than food manufacture
b (1) :  foliage <trees in full leaf>
(2) :  the leaves of a plant as an article of commerce
:  something suggestive of a leaf: as
a :  a part of a book or folded sheet containing a page on each side
b (1) :  a part (as of window shutters, folding doors, or gates) that slides or is hinged
(2) :  the movable parts of a table top
c (1) :  a thin sheet or plate of any substance :  lamina
(2) :  metal (as gold or silver) in sheets usually thinner than foil (3) :  one of the plates of a leaf spring
leaf·less \ˈlēf-ləs\ adjective
leaf·like \ˈlēf-ˌlīk\ adjective

Examples of LEAF

  1. I heard the rustle of the autumn leaves.
  2. a pile of dead leaves
  3. The trees drop their leaves in the fall, and new leaves grow again in the spring.
  4. The trees have not yet come into leaf.

Illustration of LEAF

Origin of LEAF

Middle English leef, from Old English lēaf; akin to Old High German loub leaf
First Known Use: before 12th century

Other Botany Terms

annual, burgeon, chloroplast, nomenclature, succulent, sylvan, xylem

Rhymes with LEAF



Definition of LEAF

intransitive verb
:  to shoot out or produce leaves <will leaf out in spring>
:  to turn over pages especially to browse or skim <leaf through a book>
transitive verb
:  to turn over the pages of

Examples of LEAF

  1. <we must have spent hours leafing through wallpaper books before we found something we both liked>

First Known Use of LEAF


Related to LEAF

LEAF Defined for Kids


noun \ˈlēf\
plural leaves \ˈlēvz\

Definition of LEAF for Kids

:  one of the usually flat green parts that grow from a plant stem and that functions mainly in making food by photosynthesis
:  foliage <The trees are in full leaf.>
:  a single sheet of a book containing a page on each side
:  a part that can be added to or removed from a table top
leaf·less \ˈlēf-ləs\ adjective
leaf·like \ˈlēf-ˌlīk\ adjective



Definition of LEAF for Kids

:  to grow leaves <The trees will leaf out in the spring.>
:  to turn the pages of a book
Medical Dictionary


noun \ˈlēf\

Medical Definition of LEAF

:  a thin layer or sheet of tissue <the anterior leaf of the coronary ligament>
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