The ornamental design for a displayscreen or portion thereof with a graphicaluserinterface for a communications terminal, as shown and described.
FIG. 1 is a front view of a first embodiment of a display screen or portion thereof with a graphical user interface showing the new design;
FIG. 2 is a front view of a second embodiment thereof;
FIG. 3 is a front view of a third embodiment thereof; and,
FIG. 4 is a front view of a fourth embodiment thereof.
The broken lines illustrate the display screen or portion thereof and form no part of the claimed design. The broken lines illustrate portions of the graphical user interface and form no part of the claimed design.