9. The system of claim 8 , wherein determining when the significant word usage change has occurred further comprises comparing the first group of utterances to a third group of utterances spoken by distinct speakers who are not part of the particular group of speakers.
8. The system of claim 7 , wherein determining when the significant word usage change has occurred further comprises comparing: identifying a first group of utterances from a first time of the plurality of time periods, the first group of utterances having been spoken by a particular group of speakers; identifying a second group of utterances from a second time of the plurality of time periods, the second group of utterances having been spoken by the particular group of speakers; and when a comparison of the first group of utterances to the second group of utterances indicates the distinctions are above a threshold, identifying that a significant word usage change has occurred.