There isn't a true synonym for "meniscus" in the scientific context, as it refers to a specific phenomenon. However, depending on the context, you could use terms that describe the shape or appearance of a meniscus, such as:

* Concave surface: This describes the curved shape of a meniscus in liquids that are attracted to the container walls (e.g., water in a glass).

* Convex surface: This describes the curved shape of a meniscus in liquids that are repelled by the container walls (e.g., mercury in a glass).

* Curvature: This is a general term that encompasses both concave and convex surfaces.

* Crescent: This term can be used metaphorically to describe the shape of the meniscus.

* Lens: This term is used in physics and optics to describe a curved surface that refracts light, which is analogous to the behavior of a meniscus.

The best substitute will depend on the specific context and what you want to emphasize.