Definition

1. Adjective:

   • Situated or occurring beneath the surface of the earth: Refers to something located or happening below ground level.
   • Operating or done in secret, especially for political purposes: Refers to activities, organizations, or movements that are hidden, clandestine, or subversive.

2. Adverb:

   • Beneath the surface of the earth: Describes the location or movement of something below ground.
   • In or into secrecy or hiding: Describes the state or action of operating in a concealed or clandestine manner.

3. Noun:

   • A subway system: An electric railway that operates in tunnels beneath a city.
   • A secret organization or movement: A group working covertly, often to oppose a government or ruling power.

Usage Examples

• Adjective:

  • The city has an extensive underground network of pipes and cables.
  • During the war, he was part of the underground resistance movement.

• Adverb:

  • The roots of the plant spread underground.
  • The political activists were forced to go underground to avoid arrest.

• Noun:

  • I take the underground to work every day; it's very fast.
  • She was a key member of the anti-fascist underground.

Advanced Usage

• "to go underground": to go into hiding or to begin operating secretly.
  • After the coup, the opposition leaders had to go underground.
• "underground press": secret or unofficial newspapers or publications, often critical of the government.
  • The underground press played a vital role in spreading information during the dictatorship.

Variants and Related Words

• Undergrounder (n): A person who is part of an underground movement or who lives an alternative, non-mainstream lifestyle.
• Underground (as a cultural adjective): Relating to artistic, musical, or social movements that are avant-garde, experimental, or outside the mainstream.
  • The band started in the underground music scene before achieving mainstream success.

Synonyms

• Adjective (secret): Clandestine, covert, secret, subversive.
• Adjective (below ground): Subterranean, belowground.
• Noun (railway): Subway, metro, tube.
• Noun (secret group): Resistance, clandestine organization.

Related Phrases

• Underground economy: Economic activity that is not officially recorded or taxed; black market.
  • A significant portion of the country's transactions occur in the underground economy.
• Underground art: Art that is experimental and not commercially oriented.
  • The gallery specializes in showcasing underground art.

Idioms

• To drive something underground: To force an activity or organization to operate in secret.
  • Harsh new laws drove the protest movement underground.

Adjective

1. conducted with or marked by hidden aims or methods
   • clandestine intelligence operations
   • cloak-and-dagger activities behind enemy lines
   • hole-and-corner intrigue
   • secret missions
   • a secret agent
   • secret sales of arms
   • surreptitious mobilization of troops
   • an undercover investigation
   • underground resistance
2. under the level of the ground
   • belowground storage areas
   • underground caverns

Adverb

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

Noun

1. 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'
2. a secret group organized to overthrow a government or occupation force