The delete watch API removes a watch from Watcher.
DELETE _watcher/watch/<watch_id>
When the watch is removed, the document representing the watch in the .watches
index is gone and it will never be run again.
Please note that deleting a watch does not delete any watch execution records related to this watch from the watch history.

Deleting a watch must be done via this API only. Do not delete the
            watch directly from the .watches index using the Elasticsearch
            DELETE Document API. When Elasticsearch security features are enabled, make
            sure no write privileges are granted to anyone over the .watches
            index.
watch_id (required)
You must have manage_watcher cluster privileges to use this API. For more
information, see Security Privileges.
The following example deletes a watch with the my-watch id:
DELETE _watcher/watch/my_watch
Response:
{
   "found": true,
   "_id": "my_watch",
   "_version": 2
}