Once you set the TextTrimming property of GridViewDataColumn to WordEllipsis, this mode is applied when the contents overflow the content area and works properly when you resize a column. Can you please share some more information about your settings,some code snippets if possible and the grid version you use?
I have prepared an example that you can use for a test. Feel free to modify it and sent it back to me if needed.
All the best,
the Telerik team