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Book Glossary

underground

Dictionary definition · underground

noun

  1. a secret group organized to overthrow a government or occupation force
  2. an electric railway operating below the surface of the ground (usually in a city)"in Paris the subway system is called the ‘metro’ and in London it is called the ‘tube’ or the ‘underground’"

adjective

  1. under the level of the ground"belowground storage areas"
  2. conducted with or marked by hidden aims or methods"clandestine intelligence operations"

adverb

  1. in or into hiding or secret operation"the organization was driven underground"
  2. beneath the surface of the earth"water flowing underground"

Similar words

belowgroundresistanceclandestinecloak-and-daggerhole-and-cornerhugger-muggerhush-hushsecretsurreptitiousundercover

Source: Open English WordNet (CC BY 4.0).