Transpiration is the process by which aerial part of the plant (mainly leaves) looses water in the form of water vapour.

Transpiration is termed on the basis of its occurrence through the plant like stomata, cuticle, and lenticles and called as stomatal, cuticular, and lenticular transpiration.

Cuticle is a layer of wax covering over a leaf and is primarily composed of both wax and cutin. It is meant to check transpiration.

Lenticels are the small opening in the bark of the plants, mainly in stem and root and allow the exchange of gases between the atmosphere and the inner cells.

Stomatal transpiration accounts for 90% of total transpiration done by plants while cuticular transpiration is 5-10% and lenticular transpiration is 1-5%.