A computer-implemented method, system using at least one computing device, and computer program product are disclosed for linking an ontology provided by a content service with a word expansion ontology. The content service ontology is referred to as a category ontology and the word expansion ontology is referred to herein as a lexical ontology. A user may provide an input such as an input command to an application. The input command is processed by a natural language processing engine to derive the user's intent and to extract relevant entities embodied in the command. The NLP engine may create a composite concept set containing multiple permutations of the concepts (entities extracted) and provide the composite concept set to a concept mapper. The concept mapper applies searches an ontology map and applies one or more scoring operations to determine a best match between the composite concept set and at least one category provided by the category ontology. The content service is searched using the category and the results are displayed to the user.