To plumb a body of water, you measure its depth. To plumb a house, you connect all of its pipes. To make carpentry plumb, you get it exactly vertical.

Originally, the verb plumb only meant “to measure the depth of water.” These days, if you “plumb the depths” of something, you go in deep for knowledge and experience: your Heidegger seminar may plumb the depths of German Existentialism like Jacques Cousteau plumbed the depths of the ocean.

Definitions of plumb
  1. adjective
    exactly vertical
    “the tower of Pisa is far out of plumb
    perpendicular, vertical
    at right angles to the plane of the horizon or a base line
  2. noun
    the metal bob of a plumb line
    synonyms: plumb bob, plummet
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    type of:
    a hanging weight, especially a metal ball on a string
  3. adverb
    conforming to the direction of a plumb line
  4. verb
    adjust with a plumb line so as to make vertical
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    type of:
    adjust, correct, set
    alter or regulate so as to achieve accuracy or conform to a standard
  5. verb
    weight with lead
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    type of:
    burden, burthen, weight, weight down
    weight down with a load
  6. verb
    measure the depth of something
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    type of:
    measure, quantify
    express as a number or measure or quantity
  7. verb
    examine thoroughly and in great depth
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    type of:
    examine minutely
  8. adverb
    completely; used as intensifiers
    synonyms: clean, plum
  9. adverb
    “fell plumb in the middle of the puddle”
    synonyms: plum
Word Family

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