caruncle

Caruncle is a term used in anatomy and botany to describe a small, fleshy outgrowth or projection arising from a mucous membrane, tissue, or seed. It is used in several different contexts across living organisms and plant seeds.

In human anatomy, the lacrimal caruncle is the small, pink, triangular area at the inner corner of the eye. It contains modified sweat and sebaceous glands and contributes to the tear film and ocular surface. It is visible on routine examination and is generally a normal, nonpathologic structure. Another anatomical use is the sublingual caruncle, a tiny papilla on the floor of the mouth near the lingual frenulum where the submandibular and sublingual ducts open, delivering saliva into the mouth.

In birds and some other animals, caruncles are fleshy, often highly vascularized protrusions on the head or neck. They can be brightly colored and swell during breeding displays or social interactions, serving in visual signaling and mate attraction.

In botany, a caruncle refers to a small, fleshy outgrowth on a seed, typically located at the hilum or micropylar region. Such caruncles may aid in water uptake, adhesion to substrates, or interactions with animals during seed dispersal. The term is used broadly across plant taxa to describe this distinct seed morphology.