1 definition by Bostonian. really.

1. weird weather dividing line.
2. divides the 2 states of Massachusetts and western mass both demographically and physically
"5 feet of snow west of 495 and sleet and rain closer to Boston"

Western Massian: "Yeah I'm from Boston"
Massachussarian: "oh no way where you from?"
Western Massian: "Hopedale"
Massachussarian: "That's West of 495...that's not even in Massachusetts.."
by Bostonian. really. February 6, 2011
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