What do you understand by the term “keyword” with respect to JCL and what is the opposite of the term?

A terminology "keyword" in various JCL statement might appear in different places and can be seen by its name, for example, MSGCLASS inside the various JOB statements. The inverse of the terminology "keyword" is known as positional words, where its significance relies upon the circumstance in the announcement. For example, in the keyword of DISP the = (NEW. CATLG, DELETE) whose importance relies upon the primary, secondary and tertiary position of terms.