subgrade
/ˈsʌbɡreɪd/noun
1A subsidiary or subordinate grade; a secondary gradation; a grade within a grade.
2 Civil Engin. In the construction of roads and other flat load-bearing surfaces: the layer (typically the prepared natural ground) lying immediately beneath the foundations.
Origin
Late 18th century. From sub- + grade.
- quarto
- Quartodeciman
- Quartodecimanism
- quart pot
- quart-pot tea
- quartumvirate
- quartz
- quartz clock
- quartz crystal
- quartz glass
- quartz gold
- quartz-halogen
- quartziferous
- quartzin
- quartzine
- quartz-iodine
- quartzite
- quartzitic
- quartz lamp
- quartzless
- quartz-locked
- quartzofeldspathic
- quartzoid
- quartzose
- quartzous