A North-South dialogue

It's not necessarily how fast or how slowly you speak that tells a listener whether you're a Northerner or a Southerner.

Dr. Raven McDavid of the University of Chicago argues that tempo of speech has nothing to do with ''drawling'' or ''clipping'' one's words. Those who clip words, the linguist says, can speak slowly, while those who drawl their vowels can sometimes ''talk pretty fast.''

Often more telltale are the words and phrases one uses and the way they're pronounced. If you say ''gangway'' for the space between two apartment buildings , for instance, you're probably from Chicago. What is ''tonic'' in New England is usually ''pop'' in the Midwest. Many New Englanders and New Yorkers have long referred to a front porch as a ''stoop.'' For reasons Dr. McDavid can only put down to the modeling of Savannah brownstones after those in New York City and the possible recruitment of New York architects for the job, the word ''stoop'' for ''porch'' is also used in the Savannah Valley of Georgia.

Homonyms can be a giveaway. Many Southerners, McDavid says, pronounce ''pin'' and ''pen'' the same. Bostonians and New Yorkers tend not to bother with the ''wh'' sound, says McDavid, so that ''wear'' and ''where'' are apt to sound alike. But a few miles can often make a large difference. If Bostonians who sometimes take their clothes to the ''cleanser'' are prone to pronounce ''cot'' and ''caught'' the same, for instance, don't expect the same habit to prevail in nearby Providence, R.I. The words have separate pronunciations there.

The possibilities for regional variation, particularly with food, appear to be endless. In his research, McDavid found 42 different words and phrases in North Carolina and Virginia alone to describe what most of the United States would call ''deep-dish apple pie.''