subgrade

[ suhb-greyd ]

noun

1. the prepared earth surface on which a pavement or the ballast of a railroad track is placed or upon which the foundation of a structure is built.

adjective

1. beneath the finished ground level of a project.

subgrade

/ ˈsʌbˌɡreɪd /

noun

1. the ground beneath a roadway or pavement

Word History and Origins

Origin of subgrade¹

First recorded in 1895–1900; sub- + grade

Example Sentences

Some engineers advocate that in preparing the subgrade, the earth be thoroughly rolled; others prefer not to roll the subgrade.

From Project Gutenberg

The earth subgrade is brought to the proper elevation and cross section and is thoroughly rolled.

From Project Gutenberg

Its location is in the centre of the tunnel, 41/2 feet above subgrade, and 11/2 feet above the road bed.

From Project Gutenberg

In each grade and subgrade date of commission, appointment, or warrant determines the order of precedence.

From Project Gutenberg

The pavement laid was bitulithic and the subgrade was an old macadam road built by the County.

From Project Gutenberg