Diapohja
Diapohja is a term of Finnish origin that broadly refers to the bottom layer or base of something. While it can be used in a general sense, it often appears in specific contexts within various fields.
In geology and soil science, diapohja can describe the substrate or bedrock beneath a layer of soil.
Within construction and engineering, diapohja relates to the foundation or base upon which a structure is built.
The term can also be found in more colloquial uses, referring to the bottom of a container,