property Items.CellToolTip([Item as Variant], [ColIndex as Variant]) as String

Retrieves or sets a value that indicates the cell's tool tip text.

TypeDescription
Item as Variant A long expression that indicates the item's handle.
ColIndex as Variant A long expression that indicates the cell's handle or the column's index, a string expression that indicates the column's caption or the column's key.
String A string expression that indicates the cell's tooltip. 

By default, the CellToolTip property is "..." (three dots). If the CellToolTip property is "..." the control displays the cell's caption if it doesn't fit the cell's client area. If the CellToolTip property is different than "...", the control shows a tooltip that displays the CellToolTip value.  The control  fires the ToolTip event when the column's tooltip is about to be displayed. Use the ToolTipWidth property to specify the width of the tooltip window. Use the ShowToolTip method to display a custom tooltip.

The tooltip supports the following HTML tags:

Note: The intersection of an item with a column defines a cell. Each cell is uniquely represented by its handle. The cell's handle is of HCELL type, that's equivalent with a long type. All properties of Items object that have two parameters Item and ColIndex, that refers a cell.