Hollow and Sag

Hollow noun - A sunken area forming a separate space.

Sag and hollow are semantically related in convex topic. In some cases you can use "Sag" instead a noun "Hollow", when it comes to topics like empty or dented area.

Nearby Words: hollowed, hollowing, hollowly

Sag noun - The extent to which something hangs or dips below a straight line.

Hollow and sag are semantically related in drop topic. Sometimes you can use "Hollow" instead a noun "Sag", if it concerns topics such as convex.