What does the $ in property name mean in ActionScript 3 (or JavaScript)

Question

I saw this code recently,

    public function CursorManager($target:InteractiveObject, $cursor:String) {
        _target=$target;
        _cursor=$cursor;
        _target.addEventListener(MouseEvent.ROLL_OVER, onOver);
        _target.addEventListener(MouseEvent.ROLL_OUT, onOut);
    }

Why is this person using the $ in the parameter $target? Does it hold any significant meaning? I've seen this in JavaScript as well.

UPDATE:
Is it possible it was used to denote static or constant variable? It does not appear to be used as static in this example.

UPDATE 2:
I found some code in the Flex UIComponent class that uses $width, $height. I've added an answer.

Answer 1

In this example I would say author uses $ prefix to identify variable that comes from outside (function parameter) and prefix _ to identify variable that belongs to the this function or entire class.

So the answer is NO, it doesn't hold any significant meaning. It is done for convenience only . You may want to look into code naming conventions to learn more about that.

Answer 2

When I code JavaScript I use this notation for jQuery-Objects like this:

var $target = $(event.target);
$target.hide();

Others may use this differently.

Answer 3

As Max stated, "the answer is NO, it doesn't hold any significant meaning. It is done for convenience only." but I want to add more. It is not treated any differently by the compiler (as far as I know) but in Flex it is used to signify a base property, it's final and cannot be overridden that is a reflection of a native player implementation.

For example, in the property $scaleX it states:

/**
 *  This property allows access to the Player's native implementation
 *  of the <code>scaleX</code> property, which can be useful since components
 *  can override <code>scaleX</code> and thereby hide the native implementation.
 *  Note that this "base property" is final and cannot be overridden,
 *  so you can count on it to reflect what is happening at the player level.
 */

The $width property is the same:

/**
 *  @private
 *  This property allows access to the Player's native implementation
 *  of the 'width' property, which can be useful since components
 *  can override 'width' and thereby hide the native implementation.
 *  Note that this "base property" is final and cannot be overridden,
 *  so you can count on it to reflect what is happening at the player level.
 */

mx_internal final function get $width():Number
{
    return super.width; // UIComponent extends FlexSprite which extends Sprite
}

All of the properties that begin with $ in the UIComponent class reflect these attributes.