“+ noun
Etymology: sub- + structure
: understructure , groundwork : as
a. : the foundation of a building or other structure
b. : the earth roadway supporting the ballast and track of a railway line
“+ noun
Etymology: sub- + structure
: understructure , groundwork : as
a. : the foundation of a building or other structure
b. : the earth roadway supporting the ballast and track of a railway line
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012