Velum

Part of speech: noun

Pronunciation: /ˈviː.ləm/

Definitions

1. A delicate membrane that acts as a covering or partition in biological systems
2. A thin layer serving to delineate or protect spaces within various organisms
3. A fine, sheet-like membrane that separates or covers parts within living organisms

Etymology: Anatomists borrowed "velum" straight from Latin, where it meant a cloth, covering, awning or curtain, so the membranes it names were first pictured as something like a veil or sail. The Latin word traces back through Proto-Italic to an older root, *weg-, associated with weaving, and that same family produced the English "veil". The two words are doublets: they split from one ancestor, one arriving through French as "veil" and the other taken directly from Latin as the technical term "velum". In anatomy the term is most familiar from the soft palate, the fleshy flap at the back of the mouth, which is often called the velum. Its shape suggests a curtain drawn across an opening, which is the picture the Latin word already carried.