leaflet

plant anatomy

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June 30, 2026

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A leaflet is a division of a compound leaf, which is a leaf where the blade is divided into two or more distinct parts on a common axis. These leaflets can themselves be compound. A leaflet can also refer to a small or young foliage leaf, or a leaflike organ in other contexts, such as heart valves.12

Additionally, "leaflet" can refer to a small, often folded, printed sheet intended for free distribution, similar to a brochure or flyer. In plant anatomy, distinguishing between simple (undivided) and compound (divided) leaves, where leaflets are present, is important for identifying plant species.2345

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angiosperm
Leaves
…two or more subunits called leaflets: in palmately compound leaves, the leaflets radiate from a single point at the distal end of the petiole; in pinnately compound leaves, a row of leaflets forms on either side of an extension of the petiole called the rachis. Some pinnately compound leaves branch…
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…two or more subunits called leaflets: in palmately compound leaves, the leaflets radiate from a single point at the distal end of the petiole; in pinnately compound leaves, a row of leaflets forms on either side of an extension of the petiole called the rachis. Some pinnately compound leaves branch…
Read More