Boilerplate

Etymology

In 19th-century printing, “boiler plate” was the steel plate of a boiler, and by extension the ready-made metal printing plates syndicates shipped to newspapers with pre-set text. The word came to mean any stock, unchanging passage, then the standard clauses of a contract.

noun · /BOY-ler-plate/
Standardized, reusable text — especially in contracts — that appears unchanged across many documents.
What it names
The fill-in-the-blanks legal or written scaffolding nobody drafts fresh and few actually read.
Example
The lease was mostly boilerplate, with only the rent and dates filled in.
Related idea
Boilerplate is standardized reusable wording; a caveat is a specific warning or qualification inserted into a document, and legalese names the dense professional style such text is often written in.