A system for indicating a speaker is likely to be misunderstood by at least one listener from a group of listeners. The system includes a computer interface configured to receive lexicon information from the group of listeners. The lexicon information includes words encountered by each of the listeners from the group of listeners and a word count associated with each of the words. A computer with at least one central processing unit is configured to determine when the word count corresponding to a spoken word from the speaker is below a threshold count. A transducer coupled to the computer is configured to signal the speaker that the spoken word has likely been misunderstood by the listener when the word count corresponding to the spoken word is below the threshold count.