underground adjective, adverb (BELOW EARTH)
Moles live underground.
- He suffers from claustrophobia so he never travels on underground trains.
- Ten miners were trapped underground when the roof of the tunnel fell in.
- Electrical power is supplied by underground cables.
- Planes bombed the guerrilla positions yesterday in an attempt to flush out snipers from underground tunnels.
- His grandfather had bought the land as an investment, guessing that there might be gold underground.
underground adjective, adverb (SECRET)
underground noun (TRANSPORT)
underground noun (PEOPLE)
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