How to change column name in export?

Eitan

I would like to change the name of the column "Severity" to "Severe" when exporting to CSV. Is there any way to do this?
Right now, my code looks like this:

opentable = $("#open").dataTable( {
        dom: "Bfrtip",
        "data": openData,
        "columns": [{
            data: "severity", render: function (data, type, row) {
                if (type === 'export') {
                            return data;
                        } else {
                            return ...; 
                        }
            }],
         "paging": true,
         "searching": true,
         buttons : [{
             extend: 'csv',
             exportOptions: {
                 columns: [0,1,2,3,4,5,6,7,8,9,10], orthogonal: 'export'
             }
          }]
        });