Sink

fall or drop to a lower place or level; "He sank to his knees"

pass into a specified state or condition; "He sank into Nirvana"

go under, "The raft sank and its occupants drowned"

descend into or as if into some soft substance or place; "He sank into bed"

plumbing fixture consisting of a water basin fixed to a wall or floor and having a drainpipe

dip: appear to move downward; "The setting sun sank below the tree line"

(technology) a process that acts to absorb or remove energy or a substance from a system; "the ocean is a sink for carbon dioxide"

sinkhole: a depression in the ground communicating with a subterranean passage (especially in limestone) and formed by solution or by collapse of a cavern roof

slump: fall or sink heavily; "My spirits sank"

bury: embed deeply; "She sank her fingers into the soft sand"