argill-
combining form 
or argilli- or argillo-
Etymology: Middle English argill-, from Latin, from argilla 
1. : clay 
< argilliferous >
< argilloid >
2. : argillaceous and 
< argilloarenaceous >
or argilli- or argillo-
1.
< argilliferous >
< argilloid >
2.
< argilloarenaceous >