Wikipedia:

Leaf

Summary:

an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. As an evolutionary trait, the flatness of leaves works to expose the chloroplasts to more light and to increase the absorption of carbon ...  (40 of 4083 words, 27 images)

Link:

http://en.wikipedia.org/wiki/Leaf  [cite]

Merriam-Webster:

foliage | foliaged

Summary:

a representation of leaves, flowers, and branches for architectural ornamentation | the aggregate of leaves of one or more plants | a cluster of ...  (22 of 132 words, 3 senses, 1 etymology, pronunciation)

Link:

http://www.merriam-webster.com/dictionary/foliage  [cite]

Encarta:

foliage | foliaged [adjective]

Summary:

the leaves of a plant or tree | architectural ornamentation based on leaves and stems  (14 of 45 words, 2 senses, 1 etymology, pronunciation)

Link:

http://encarta.msn.com/dictionary 1861612677/definition.html  [cite]

Random House:

foliage | leafage

Summary:

the leaves of a plant, collectively; leafage. | leaves in general. | the representation of leaves, flowers, and branches in painting, architectural ...  (20 of 30 words, 3 senses, pronunciation)

Link:

http://dictionary.infoplease.com/foliage  [cite]

Wiktionary:

foliage | foliages [plural]

Summary:

The leaves of plants | A cluster of leaves | An architectural ornament representing foliage.  (13 of 19 words, 3 senses, 1 etymology)

Link:

http://en.wiktionary.org/wiki/foliage  [cite]