Final answer:
Service packs are collections of well-tested Windows updates combined into a single installation package, including security updates, bug fixes, and enhancements.
Step-by-step explanation:
The term for multiple Windows updates that have been packaged together into one installation and are well tested is known as service packs. Service packs are a collection of updates, fixes, and/or enhancements to a software program delivered in the form of a single installable package. They often include security updates, bug fixes, and performance improvements that have been cumulatively gathered since the release of the previous update.