1. A system, comprising: a user context language model engine including, logic to cause a processor to associate one or more key words with each of a plurality of types of user context information, logic to cause the processor to identify user context information associated with each of a plurality of users, and logic to cause the processor to generate a user context vocabulary of words, for each of the plurality of users, from the key words associated with the corresponding user context information; a product language model engine including, logic to cause the processor to associate one or more key words with each of a plurality of product categories, and logic to cause the processor to generate a product vocabulary of words from the key words corresponding to the product categories; an acoustic model engine to convert user input speech to a first set of one or more words; and a word selection engine to select a second set of one or more words from one or more of a corresponding one of the user context vocabulary of words and the product vocabulary of words that correlate to the first set of one or more words.