Merriam-Webster's Collegiate® Dictionary, 11th Edition
DISJUNCTIVE
I. adjective
Date: 15th century
1. relating to, being, or forming a logical disjunction, expressing an alternative or opposition between the meanings of the words connected , expressed by mutually exclusive alternatives joined by or , marked by breaks or disunity , stressed and not attached to the verb as an enclitic or proclitic, disjunctively adverb
II. noun
Date: 1530
a disjunctive conjunction