Sinus (botany)

In botany, a sinus is a space or indentation between two lobes or teeth, usually on a leaf.^[1] The term is also used in mycology. For example, one of the defining characteristics of North American species in the Morchella elata clade of morels is the presence of a sinus where the cap attaches to the stipe.^[2]

The area between the two lobes of this Cyclamen persicum leaf is a sinus.

See also

• Leaf shape
• Sulcus (morphology)