Dictionary definition · plumb
noun
- the metal bob of a plumb line
verb
- measure the depth of something
- weight with lead
- examine thoroughly and in great depth
- adjust with a plumb line so as to make vertical
adjective
- exactly vertical"the tower of Pisa is far out of plumb"
adverb
- completely; used as intensifiers"clean forgot the appointment"
- conforming to the direction of a plumb line
- exactly"fell plumb in the middle of the puddle"
Source: Open English WordNet (CC BY 4.0).