The pango-ellipsize-mode enumeration describes what sort of (if any) ellipsization should be applied to a line of text. In the ellipsization process characters are removed from the text in order to make it fit to a given width and replaced with an ellipsis.

(define-g-enum "PangoEllipsizeMode" pango-ellipsize-mode
  (:export t
   :type-initializer "pango_ellipsize_mode_get_type")
  (:none 0)
  (:start 1)
  (:middle 2)
  (:end 3))  

:none

No ellipsization.

:start

Omit characters at the start of the text.

:middle

Omit characters in the middle of the text.

:end

Omit characters at the end of the text.