The word contains two types of meanings, some have lexical meaning, that is, they refer to reality, concrete aspects of it (subtle, adjectives, verbs and some adverbs). This means that when we say table, for example, this sequence of sounds refers to an object that is used to write, to work, to eat, that has legs and that can be made of wood or other material and present different forms. This type of meaning allows to organize the words in areas of meaning, that is, in sets and subsets called lexical fields or semantic fields.
There are, on the other hand, other words that do not have this kind of meaning, do not refer to any thing, quality, action or any other aspect of objective reality. Its meaning is only functional or grammatical. For example, since the article is an identifier of the noun, prepositions can indicate relations of direction (a), destiny (for), provenance (from), instrument (with), opposition (against). Some conjunctions mean union (and, e), other opposition (but, more, though) or cause (because). The meaning of these words is strictly grammatical or functional, because they indicate only a grammatical function.
References:
- Lacau- Rosstt.i (1980). Nuevo Castellano 1: Lengua y Literatura. Buenos Aires: Kapelusz S.A.
- Nacional.Falcón, J. y otros (2000). Lengua Española. Caracas: Fedeupel (Serie Azul).