Definition: descend into or as if into some soft substance or place Example:
He sank into bed.
She subsided into the chair.
sink (n)
Definition: a depression in the ground communicating with a subterranean passage (especially in limestone) and formed by solution or by collapse of a cavern roof
Definition: a depression in the ground communicating with a subterranean passage (especially in limestone) and formed by solution or by collapse of a cavern roof