labelWidth

the width of the label

number| string labelWidth;

webix.ui({
    view:"combo", 
    label: 'Fruit', 
    labelWidth:100,
    ...
})

Details

You can adjust the lable width to its content width by setting the labelWidth property to "auto":

{
    view: "text",
    label: "First Name",
    labelWidth: "auto"
}