regosol
noun
reg·o·sol ˈre-gə-ˌsäl 
-ˌsȯl
: any of a group of azonal soils consisting chiefly of imperfectly consolidated material and having no clear-cut and specific morphology
Word History
Etymology
rego- (as in regolith) + Latin solum soil — more at sole
First Known Use
1949, in the meaning defined above