labelFontFamily : String

Sets the font-family of crosshair’s label.

Default: “Calibri, Optima, Candara, Verdana, Geneva, sans-serif”
Example: “Arial, Trebuchet MS, Tahoma, sans-serif”

var  chart =  new  CanvasJS.Chart("container",
{
 .
 .
axisX:{
    crosshair:{
        enabled: true,
        labelFontFamily: "Arial",
	.
	.
    }
},
 .
 . 
});
chart.render();