NCI Dictionary of Cancer Terms The NCI Dictionary of Cancer Terms features 8,091 terms related to cancer and medicine. The search textbox has an autosuggest feature. When you enter three or more characters, a list of up to 10 suggestions will popup under the textbox. Use the arrow keys to move through the suggestions. To select a suggestion, hit the enter key. Using the escape key closes the listbox and puts you back at the textbox. The radio buttons allow you to toggle between having all search items start with or contain the text you entered in the search box. Starts with Contains Browse: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # retromolar trigone listen (reh-troh-MOH-ler TRY-gone) The small area behind the wisdom teeth. Enlarge Anatomy of the oral cavity. The oral cavity includes the lips, hard palate (the bony front portion of the roof of the mouth), soft palate (the muscular back portion of the roof of the mouth), retromolar trigone (the area behind the wisdom teeth), front two-thirds of the tongue, gingiva (gums), buccal mucosa (the inner lining of the lips and cheeks), and floor of the mouth under the tongue.