残ざん柱ちゅう

noun

pillar; residual pillar

Technical term in mining or civil engineering for a pillar of material left in place to support the roof or surrounding structure. Not a general word for architectural pillars.

• 炭たん鉱こうでは、天てん盤ばんを支ささえるために残ざん柱ちゅうを残のこすことがある。

  In coal mines, residual pillars are sometimes left to support the roof.