It takes listeners longer to determine what a word is—to understand c-a-t to be cat—when that word has lots of neighbors. That’s because when we hear a word, everything that sounds like that word becomes slightly more accessible in memory. With a large neighborhood at the ready, it is more difficult to eliminate the words that were not said; it’s harder to rule out the possibility that the talker said cut or kit or cot or cad or cap rather than cat. A word like gem, which has fewer neighbors than cat, is simply less confusable, and thus, all else being equal, requires less work to identify.
Jessica Love on word neighborhoods. Read.
