Ad Hoc

Definitions

Created or done for a specific immediate purpose rather than as part of a permanent, well-structured system. In engineering culture, ad hoc solutions are common under time pressure but often accumulate maintenance cost if they become permanent.
In plain English: Improvised for a specific situation rather than built as a general permanent solution.
Example: "The ad hoc reporting script solved the audit request quickly, but six months later it had quietly become a critical dependency with no tests."