/roohm"euhn pil"euhr, room"-/ , adj. Mining.
noting a means of extracting coal or other minerals from underground deposits by first cutting out rooms, then robbing the pillars between them; pillar-and-breast. Cf. longwall .
/roohm"euhn pil"euhr, room"-/ , adj. Mining.
noting a means of extracting coal or other minerals from underground deposits by first cutting out rooms, then robbing the pillars between them; pillar-and-breast. Cf. longwall .
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012