A list of words or other data items which, for some special reason, should be ignored or bypassed by a particular data processing operation.
If you equip your search engine with a stop list containing a few common words such as "a", "the", and "and", you can decrease the full-text index size by about 20%.
A list of people who subscribe to a publication (e.g., newspaper) and no longer wish to receive it.
A list of the stops found on a particular organ.