Why Vector?

When the first time I saw “Vector”, I thought “new type?” then I found out: “oh, it’s just typed Array”.
ok I know everybody here might not the one who define “Vector” type. But I just wondering why Adobe name it “Vector” (technically) instead of Array.<type>. Using Array name might be more clear don’t you think? Vector basically is just (typed) Array.
btw, while talking about Vector, how can I create an empty Vector like this:

var myArray:Array = [1, 2, 3, 4, 5]
myArray = [] // clear the array

var myVector:Vector.<int> = new Vector.<int>();
myVector = [] // I want to clear the vector array, but this way obviously doesn't work, then how?