How to limit a table cell to one line of text using CSS?

overflow will only work if it knows where to start considering it overflown. You need to set the width and height attribute of the <td>

TAKE 2

Try adding table-layout: fixed; width:500px; to the table's style.

UPDATE 3

confirmed this worked: http://jsfiddle.net/e3Eqn/

Add the following code to your stylesheet:

table { 
  white-space: nowrap;
}