Definition - What does Leaflet mean?
In biology, a leaflet is part of a compound leaf. Specifically, a compound leaf is constructed of two or more leaflets, often three or five, although in some plants many more.
Clover, black locus, and walnut are all compound leaves comprised of three or more leaflets. Fern is also an example of a compound leaf made of multiple leaflets on a single stalk or leaf.
An aspen is an example of a simple leaf that is not comprised of multiple leaflets.
MaximumYield explains Leaflet
Photosynthesis and transpiration occur exactly the same in compound leaf plants of multiple leaflets and the simple-leafed plants.
However, the compound leaf has a slight advantage over the simple leaf because compound leaves often have much longer petioles, which are the green stalk part that connects a leaf to the stem of the plant.
Because of this, a plant is better able to direct or place the leaf in direct sunlight. The greater the available surface to collect sunlight, the better able a plant is to gather sunlight and produce energy.