Hide axis and gridlines Highcharts

For the yAxis you'll also need:

gridLineColor: 'transparent',

Just add

xAxis: {
   ...  
   lineWidth: 0,
   minorGridLineWidth: 0,
   lineColor: 'transparent',
   ...          
   labels: {
       enabled: false
   },
   minorTickLength: 0,
   tickLength: 0
}

to the xAxis definition.

Since Version 4.1.9 you can simply use the axis attribute visible:

xAxis: {
    visible: false,
}

If you have bigger version than v4.9 of Highcharts you can use visible: false in the xAxis and yAxis settings.

Example:

$('#container').highcharts({

    chart: {
        type: 'column'
    },

    title: {
        text: 'Highcharts axis visibility'
    },

    xAxis: {
        visible: false
    },

    yAxis: {
        title: {
            text: 'Fruit'
        },
        visible: false
    }

});