plumb
Cross references: 1. vertical 1. plumb or off plumb \'pl*m\ n [ME, fr. (assumed) OF plomb, fr. OF plon lead, fr. L plumbum] 1: a lead weight attached to a line and used to indicate a vertical directi on 2: a lead or other weight : out of vertical or true - out of plumb 2. plumb av 1: straight down or up : VERTICALLY 2: DIRECTLY, EXACTLY; also : IMMEDIATELY chiefly dial 3: COMPLETELY, ABSOLUTELY 3. plumb vb [back-formation fr. plumber] 1: to weight with lead 2a: to measure the depth of with a plumb 2b: to examine minutely and critically 3: to adjust or test by a plumb line 4: to seal with lead 5: to supply with or install as plumbing : to work as a plumber 4. plumb aj 1: exactly vertical or true 2: DOWNRIGHT, COMPLETE
Webster's English Dictionary