monolithic
adj.adj. describing something that is made of one single piece of stone or material. It can also describe a system or organization that is very large and difficult to change.
adj. consisting of a single piece of stone or material; by extension, describing a structure or organization that is large, complex, and resistant to internal change.
The ancient temple was built from a single monolithic block of stone.
The company's monolithic structure made it difficult for the new manager to implement any significant changes to the workflow.
While the monolithic architecture of the cathedral provides a sense of overwhelming stability, it also makes the building vulnerable to structural failure if any single pillar is compromised.
From French monolithique. By surface analysis, monolith + -ic.