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underground railroad

A secret network for moving and housing fugitives, as in There's definitely an underground railroad helping women escape abusive husbands. This term, dating from the first half of the 1800s, alludes to the network that secretly transported runaway slaves through the northern states to Canada. It was revived more than a century later for similar escape routes.

go underground

in. to go into hiding; to begin to operate in secret. The entire operation went underground, and we heard no more about it.
See also: underground
References in periodicals archive ?
Table 1: Europe Underground Gas Storage Key Statistics, 2013 10 Table 2: Europe, Country wise Underground Gas Storage Capacity (mmcf), 2013 10 Table 3: Europe, Company wise Underground Gas Storage Capacity (mmcf), 2013 11 Table 4: Europe, Underground Gas Storage Capacity in Russia (mmcf), 2013 13 Table 5: Europe, Underground Gas Storage Capacity in Ukraine (mmcf), 2013 14 Table 6: Europe, Underground Gas Storage Capacity in Germany (mmcf), 2013 15 Table 7: Europe, Underground Gas Storage Capacity in Germany (mmcf), 2013 (Contd.
The report covers customer expectations, storms and damage, reliability of overhead and underground electrical systems, utility infrastructure, benefits and challenges of undergrounding, costs of undergrounding, state policies and utility approaches to under-grounding, and state undergrounding studies.
For years, the mining industry had sought to reduce the quarterly inspections that the 1969 health and safety act required at all underground coal mines.
This activity aims to better determine the location and extent of underground mine workings, in addition to evaluating the potential to mine remnant gold mineralization as part of an open-pit mining operation.
TCE has been found in the underground water at concentrations as high as 7,000 parts per billion.
Before 1863, the Underground Railroad was a system of cooperation among African American slaves, free African Americans, abolitionists, sympathetic whites and Native Americans to help slaves escape their bonds and claim the promise of freedom.
InSAR is a "promising technique" for finding the sites of underground nuclear tests, says William S.
After the Greenwich Village blast, Boudin and fellow "Weatherman" Cathy Wilkerson fled the building and went underground.
Schlosser posits that the porn biz, like other underground industries, was responsible for innovations in everyday American life, including "the successful launch of the VCR.
Fools in the underground are gonna start signing major deals and get bigger.
Few underground mines at that time had adequate ventilation, and miners described thick smoke that made them acutely ill and long hours of working in heavy dust conditions.
In January, 1997, Cardinal Kung Foundation released to the news media an internal document of the Chinese government detailing procedures to eradicate the underground Catholic Church, including the use of "resolute, decisive and organized measures.
For instance, Maine passed a law to regulate all underground petroleum storage tanks regardless of their size or use.
The line will also have wider benefits for Londoners, bringing the Underground to areas of the city that previously lacked an efficient metro link, such as North Greenwich and Bermondsey.
Here, a collection of independent entrepreneurs created underground drug distribution networks serving customers from throughout the city.
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