A more thorough explanation:

A patent disclaimer is a statement made by a patent applicant to relinquish one or more claims to their invention. This is done to save the remainder of the patent application from being rejected. It is a renunciation of one's legal right or claim to a patent.

For example, if a patent applicant has made a claim that is found to be invalid, they may choose to disclaim that claim in order to still be granted a patent for the remaining claims. This allows them to protect their invention without having the entire application rejected.

Another example of a patent disclaimer is a terminal disclaimer. This is a statement made by a patent applicant to shorten the term of their patent. It may be required in cases where an inventor has created an obvious variation on an existing patent. By agreeing that both patents will expire on the same day, the inventor can avoid a double-patenting rejection.

Overall, a patent disclaimer is a way for a patent applicant to protect their invention while also acknowledging any limitations or invalid claims. It is an important part of the patent application process and can help ensure that the patent is granted in a timely manner.