AdjustmentBox[box, opts] displays with the placement of box adjusted using the options given.
In the notebook front end, AdjustmentBox objects can typically be inserted and modified using , , and . These keys move your current selection by one pixel at the current screen magnification.
The following options can be given:
Horizontal motion specifications are in ems; vertical ones in x-heights.
Motion specifications can be either positive or negative numbers.
Positive margin specifications increase the spacing around box; negative ones decrease it.
Moving the baseline affects for example vertical alignment in a RowBox.
Top and bottom margins affect for example placement in a FractionBox or an OverscriptBox.
In StandardForm and InputForm input, AdjustmentBox is by default ignored, so that AdjustmentBox[box, opts] is interpreted just as box would be.
Inserting an explicit spacing character such as \[ThinSpace] can have the same effect for display as AdjustmentBox, but the spacing character by default affects interpretation.
AdjustmentBox[box, opts] uses the options given only to adjust the position of box itself. Unlike StyleBox, it does not propagate the options to subboxes.
See The Mathematica Book: Section 2.8.11.
See also: StyleBox, GridBox, ScriptBaselineShifts.