1. A method comprising: providing a lexicon; receiving a spoken utterance of a word or phrase; after receiving the spoken utterance, obtaining an initial pronunciation for the spoken utterance; after obtaining the initial pronunciation, modifying the initial pronunciation to generate a plurality of alternative pronunciations; using the received spoken utterance to score each of the pronunciations among the plurality of alternative pronunciations; identifying a highest scoring pronunciation among the plurality of alternative pronunciations; and updating the lexicon with the highest scoring pronunciation.