"Sinkhole". To undermine. 1 . Mining. A cave that is dug into the side of a hill or mountain and sometimes extended to form an underground gallery. 2 . Subsidence of the soil due to the natural or artificial occurrence of a hollow (empty space) under the soil. 3 . Do not confuse "sinkhole" with "tunnel". Tunnel: An underground road artificially opened for the "passage" of people and vehicles. Even some tunnels are aqueducts, built especially for the transport of water, and others are only for the passage of certain species of animals. According to RAE .
