SpanAdjustments

SpanAdjustments is an option for cells that determines the height and width of spanning characters.

You can fine-tune the appearance of an expression by adjusting the height and width of spanning characters. You can adjust the height and width of any character either by scaling its original value or by adding to it. SpanAdjustments {{a, b},{c, d}} means that if the original height and width are x and y, the final height is Max[ax, x + c] and the final width is Max[by, y + d].

The default setting is SpanAdjustments Automatic, which assigns an appropriate value to each character depending on its context.