Graphs of lexical relations share important specific properties with graphs of social relations. We present here a method for bringing out the hierarchical organization of a graph of synonymy of French adjectives. The lexical structure can be visualized at different scales, revealing the relevant dimensions of the semantic space at each level, from the global macrostructure to the most fine-grained local organization. The method uses the ‘small-world' structure of the graph. The graph is associated with a semantic space; each clique of the graph (in our case its maximal sets of adjectives that are all synonyms for one another) is a point of this space. This model accounts for theoretical studies on French adjectives. It also brings a new interesting light on the organisation of the French adjectival lexicon. The semantic space seems to play the same role for words that the geographical space does for humans. Words meet in the semantic space like people meet in the world. The tools presented here should apply to social graphs.