A special word, "naynaa," which occurs in the Jamul dialect of Diegueno, a Yuman language spoken in the San Diego, California, area is described. Jamul has subject-object-verb word order, and its major word classes are noun and verb. Lexical pronouns are not required. Clauses may be connected by means of switch reference marking, and/or by various other grammatical devices. "Naynaa" has four functions: as an emphatic; as an emphatic marker of co-reference between a possessor and the subject of its clause; in the flexive construction; and as an emphatic same-subject marking device in complex sentences. Its uses are described in detail. Contains 20 references. (LB)