This paper is intended to define some of the meanings of the English preposition UP, which is one of the typical polysemous forms. It discusses meanings of UP according to two basic ideas to avoid contingent misunderstanding. One is to the effect that every one of the meanings in a semantic network of a word has to share some family resemblance with at least one of the member meanings, and the other is that the selectional restrictions of the traject and the landmark of a lexical form are most useful in defining the meanings of a lexical form. The preposition UP can represent upward movement in a three dimensional physical space, subjectivized upward movement of a scanning line of vision, subjectivized upward movement of a searching line of vision, subjectivized upward supporting force, upward movement of the top point of a physical body, getting up and being synecdochically active and being static after upward movement. Up can also represent upward movements in a two dimensional geog