WSJ:

In March, Harvard University Press will publish the Dictionary [of American Regional English]’s Volume V, finishing off the alphabet with slab through zydeco, nearly half a century after the first fieldworkers fanned out in “Word Wagons” to 1,002 communities across America, administering a 1,600-item questionnaire to sometimes-suspicious, often-perplexed locals.

The fruits of their labors have been a feast for the lexicographically inclined ever since. What does a patient in the South mean when he complains of dew poison? What does a waitress in California mean when she offers you coffee and snails? Where would you go if a New Englander directed you to the willywags?

(Answers: The patient has a rash on his feet or legs. The waitress is offering you cinnamon rolls with your cup of joe. The New Englander means what others might call the boonies.)