Protuberance

Protuberance is a noun describing any part that bulges, extends, or projects outward from a surface. The word comes from Latin roots meaning to swell forward, and it is used across disciplines as a general, non-technical term for a visible outward extension or bump.

In anatomy and medicine, protuberances appear as anatomical landmarks or outgrowths. Examples include bony prominences such as the external occipital protuberance on the skull, or other protrusions of bone or soft tissue. The term can also describe abnormal or incidental bumps on the body, though more specific terminology is often preferred in clinical contexts.

In biology and microbiology, protuberances describe outward projections of cells. Amoeboid cells form pseudopods or other protrusions to move and capture food. Neurons and other cells may develop neurite-like extensions or other surface protrusions that play roles in signaling and interaction with their environment.

In geology and geography, protuberances refer to projections of rock, soil, or landforms that extend beyond surrounding terrain, such as a bulge along a coastline or a jut of rock separating a landscape from a plain.

In astronomy, protuberances or prominences are luminous extensions seen at the edge of the Sun, caused by solar plasma anchored to the solar surface and extending into the corona.

Overall, protuberance is a versatile descriptor for any outward projection or bump on a surface.