Widecreen and its companion Widesscreen are most likely to occur in video and DVD bibliographic records. Current best practice places information about aspect ratio in the 538 field, but it also may show up in an edition statement in the 250 field. New televisions are designed to show widescreen format to best advantage, so people will be looking for this word in the records. Since it probably appears only once, correct spelling is critical. Be sure the 538 field is searchable in your system. These typos come from the new typos to be added to the D list : http://faculty.quinnipiac.edu/libraries/tballard/Typoscompletenew.html
On the same page waiting to go on the E list is Widescreeen, which sounds like the perfect format for a horror movie.