Text decorations: Overline
<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" HorizontalAlignment="Center" VerticalAlignment="Center" TextElement.FontFamily="Palatino Linotype"> <TextBlock FontSize="1cm" TextWrapping="Wrap" TextAlignment="Center"> <Span TextDecorations="Overline">Overline</Span>, </TextBlock> </Window>