(adj) situated at or extending to great depth; too deep to have been sounded or plumbed; ; -Thomas Gray, Syn. unfathomed, unplumbed, unsounded, Example:the profound depths of the sea; the dark unfathomed caves of ocean; unplumbed depths of the sea; remote and unsounded caverns
n. [ F. plombier. See Plumb. ] One who works in lead; esp., one who furnishes, fits, and repairs lead pipes. [ 1913 Webster ]
2.Hence: Any worker who installs or repairs piping and related equipment for conveyance of water, gas, or drainage into or out of buildings, or within buildings to fixtures or equipment using water. The type of material used for the conduits varies with the application, and may be may be of lead, iron, copper, glass, palstic, or other material. [ PJC ]