Anglicism which expresses conformity: Yes, vale, of agreement, I think either. In Madrid some young castellanizan it in okis so that it is not so dry. Seems to have origin military and 19th century, as the U.S. military ended its reports after some battles with these acronyms: or K. I.e., 0 killed, zero dead.
* Only one "like" per meaning and day, the more "likes" the meaning will appear higher in the list