ows:KeywordsType

Unordered list of one or more commonly used or formalised word(s) or phrase(s) used to describe the subject. When needed, the optional "type" can name the type of the associated list of keywords that shall all have the same type. Also when needed, the codeSpace attribute of that "type" can reference the type name authority and/or thesaurus. 

For OWS use, the optional thesaurusName element was omitted as being complex information that could be referenced by the codeSpace attribute of the Type element.