This chapter describes how we can use dominant meaning to improve a Web-based learning environment. For sound adaptive hypermedia systems, we need updated knowledge bases from many kinds of resource (alternative explanations, examples, exercises, images, applets, etc.). The large amount of information available on the Web can play a prominent role in building these knowledge bases. Using the Internet without search engines to find specific information is like wandering aimlessly in the ocean and trying to catch a specific fish. It is obvious, however, that search engines are not intended to adapt to individual performance. Our new technique, based on dominant meaning, is used to individualize a query and search result. By dominant meaning, we refer to a set of keywords that best fits an intended meaning of the target word. Our experiments show that the dominant meanings approach greatly improves retrieval effectiveness.