New England English is not a single American dialect, but a collective term for a number of dialects and varieties that are close geographic neighbors within New England, but which differ on a spectrum that broadly divides New England English into a unique north versus south (specifically, a northern merger of the and vowels, versus a southern merger of the and vowels), as well as a unique east versus west (specifically, an eastern pronunciation of the "r" sound only before vowels, versus a western pronunciation of all "r" sounds). Regarding the former feature, all of northern New England (most famously including Boston, but going as far southeast as Cape Cod and as far north as central Maine) historically merges the open and open-mid back rounded vowels (so that, for instance, "pond" and "pawned" are pronounced the same, which is commonly called the cot–caught merger), while southern coastal New England (including Rhode Island) historically maintains a noticeable distinction between these two vowels. Regarding the second feature, all of eastern New England is historically non-rhotic (famously pronouncing "car" like "kah"), while all of western New England is historically rhotic (or ""r"-ful"). Therefore, four combinations of these two features are possible, and coincidentally all four exist among New England English speakers, largely correlated with the exact geographic quadrant in New England in which a speaker was raised.