Related to the title of this article, the first function is used as the stand point for the referential theory. In referential theory, meaning is defined as label which is in human consciousness to point out the out side world. As label, the meaning appears because of the process of observation and conclusion drawing through facts which make human possible to arrange and develop concept schemes. Therefore, put it simple, according to this view, the meaning of lexicon can be traced through its physical reference.
Moreover, the relation between lexicon and the thing it refers to is called referential relation, which becomes the part of extensionalism tradition, in which according to this tradition the meaning of word can be explained in a relation boundary between word and the thing it refers to. Further, this relation includes proper name which refers to person, such as Awin refers to a person who has written this article, noun which refers to thing, such as table refers nonliving thing made from usually wood functions to put objects on it and the couple of chair, verb which refers to action, adjective to the condition of thing or person, and adverb to the condition of certain action. Therefore, in the effort to gain meaning of lexicon by using this theory is emphasized on the observation of the out side world which can be felt by human five senses.
However, not all words/ lexicons of human language has physical reference, just say, the word: and, or, of , not, yet, no, very, in, etc.there is no evidence at all that those words refers to certain thing, or words such as: believe, want, and hope are also hard to define by this theory . This problem is getting worse if it is related to semantic categories of human perception. Since, not all categories of semantic field of human perception have physical reference. There are nine categories of semantic in human perception, those are:
This theory can explain limited only on the first to eighth but not the ninth, human senses only be able to capture those eight categories but not being which refers to abstract concept, such as sad, poverty, truth, love, etc