plumb

Short definition from Wiktionary

Noun

1. 1
   A little mass of lead, or the like, attached to a line, and used by builders, etc., to indicate a vertical direction.
2. 2
   A weight on the end of a long line, used by sailors to determine the depth of water.
3. 3
   The perpendicular direction or position.
4. 4
   Obsolete form of plum (“the fruit”).

Adjective

1. 1
   Truly vertical, as indicated by a plumb line.
2. 2
   Describing an LBW where the batsman is hit on the pads directly in front of their wicket and should be given out.

Adverb

1. 1
   In a vertical direction; perpendicularly.
2. 2
   Squarely, directly; deeply, completely.

Verb

1. 1
   To determine the depth, generally of a liquid; to sound.
2. 2
   To attach to a water supply and drain.
3. 3
   To think about or explore in depth, to get to the bottom of.
4. 4
   To use a plumb bob as a measuring or aligning tool.
5. 5
   To accurately align vertically or horizontally.
6. 6
   To seal something with lead.
7. 7
   To work as a plumber.
8. 8
   To fall or sink like a plummet.
9. 9
   To trace a road or track; to follow it to its end.
10. 10
    To position vertically above or below.

Proper noun

1. 1
   A surname.