noun
uniformitarianism
Technical term in geology and historical linguistics; the principle that the same natural laws and processes that operate now have always operated in the past.
斉一説は地質学の基本原理の一つである。
Uniformitarianism is one of the fundamental principles of geology.
From 斉一 (uniform) + 説 (theory). The exact historical derivation is uncertain; the term is a modern academic coinage.