The emission of water vapor from the leaves of plants

• The passage of gases through fine tubes because of differences in pressure or temperature

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Transpiration \Tran`spi*ra"tion\, n. [F. transpiration.] (Physiol.) The act or process of transpiring or excreting in the form of vapor; exhalation, as through the skin or other membranes of the body; as, pulmonary transpiration, or the excretion of aqueous ...

Longman Dictionary of Contemporary English Word definitions in Longman Dictionary of Contemporary English
noun EXAMPLES FROM CORPUS ▪ Apart from mysterious perfumes, the transpiration of this unusual liquid is the most frequently reported phenomenon. ▪ More than half of this disappears through evaporation or transpiration through plants. ▪ Once in the xylem, ...

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
early 15c., from Medieval Latin transpirationem (nominative transpiratio ), noun of action from transpirare (see transpire ).

WordNet Word definitions in WordNet
n. the passage of gases through fine tubes because of differences in pressure or temperature the process of givng off or exhaling water vapor through the skin or mucous membranes the emission of water vapor from the leaves of plants

Wikipedia Word definitions in Wikipedia
Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves , stems and flowers . Water is necessary for plants but only a small amount of water taken up by the roots is used for growth and metabolism. ...

Wiktionary Word definitions in Wiktionary
n. 1 (context botany English) The loss of water by evaporation in terrestrial plants, especially through the stomata; accompanied by a corresponding uptake from the roots. 2 (context physiology English) The process of giving off water vapour through the ...