Transpiration is a process in which plants release water vapor. A part of water that plants get is used to prepare their food and store in different parts of the plant. The remaining amount of water is released by plants in the form of water vapor in air. This process of releasing water vapor by plants into the air is called transpiration.

Transpiration has the following roles in plants- it cools the plant, maintain water cycle, allows absorption of water and minerals from soil and its transport in plants, allows diffusion of carbon dioxide from air for photosynthesis.