Glossary: Leaf morphology

Adaxial Facing towards the stem of a plant. The upper surface of a leaf.

Axil The angular connection between a leaf or branch and a stem Did you know? Most new side branches begin from axillary buds, which is why pruning just above a leaf node can encourage branching.

Bulb An swollen underground plant part, which stores food, usually during a dormant season, composed of scales or leaf bases. Did you know? An onion is a true bulb. Its edible layers are modified leaves that store food for the plant.

Compound Composed of two or more similar parts. A compound leaf is a single leaf composed of multiple leaflets.

Cordate Having a heart-shaped outline. Botanists use this feature to describe leaf shape, surface, edge, or arrangement, which helps with plant identification. Did you know? Redbud leaves are a familiar example of cordate leaves, with a heart-shaped outline.

Cotyledon A seed leaf. (a leaf which is part of a seed) Did you know? The number of cotyledons separates monocots from dicots — one seed leaf versus two seed leaves.

Dorsal On the back or outward surface of a leaf or other structure

Emarginate With a shallow notch at the tip. Botanists use this feature to describe leaf shape, surface, edge, or arrangement, which helps with plant identification.

Entire With a smooth even unbroken margin, usually referring to the edge of a leaf