Code:
Sub DeleteLastWord()
Dim oRng As Range
'set a range to the paragraph the cursor is in
Set oRng = Selection.Paragraphs(1).Range
'omit the paragraph break character
oRng.End = oRng.End - 1
'Collapse the range to its end
oRng.Collapse 0
'Move backwards to the first space
oRng.MoveStartUntil Chr(32), wdBackward
'Optionally include that space
oRng.Start = oRng.Start - 1
'Delete the range
oRng.Delete
lbl_Exit:
Set oRng = Nothing
Exit Sub
End Sub