21. The method of claim 6 , wherein grouping the plurality of phrases by similarity comprises: detecting each of the phrases a threshold number of times in a first context; and in response to the determination, grouping the plurality of phrases associated with a similar context.
6. The method of claim 5 , wherein the semantic group is generated by: computing differences between each of a plurality of phrases generated by an automatic speech recognition engine, each of the plurality of phrases comprising a plurality of terms; grouping the plurality of phrases by similarity; identifying locations of differences between the plurality of phrases; and defining a generalized semantic group, the generalized semantic group comprising terms at the locations of the differences between the plurality of phrases.