Synonyms and Antonyms for underground

1. underground (adj.)

under the level of the ground

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2. underground (adv.)

beneath the surface of the earth

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3. underground (n.)

an electric railway operating below the surface of the ground (usually in a city)

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4. underground (adv.)

in or into hiding or secret operation

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5. underground (n.)

a secret group organized to overthrow a government or occupation force

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6. underground (adj.)

conducted with or marked by hidden aims or methods

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