noun
: an excavator in which a small scoop moves back and forth along the underside of a vertical steel template having the form of the cross section of the ditch to be excavated
noun
: an excavator in which a small scoop moves back and forth along the underside of a vertical steel template having the form of the cross section of the ditch to be excavated
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012