under or below an object or a surface; at a lower place or level; directly beneath; "we could see the original painting underneath"; "a house with a good foundation underneath"
on the lower or downward side; on the underside of; "a chest of drawers all scratched underneath"
an open recess in a wall at the base of a chimney where a fire can be built; "the fireplace was so large you could walk inside it"; "he laid a fire in the hearth and lit it"; "the hearth was black with the charcoal of many fires"
morally degraded; "a seedy district"; "the seamy side of life"; "sleazy characters hanging around casinos"; "sleazy storefronts with...dirt on the walls"- Seattle Weekly; "the sordid details of his orgies stank under his very nostrils"- James Joyce; "the squalid atmosphere of intrigue and betrayal"