Quote from American Heritage Dictionary:

"The quality of being twofold; dichotomy."

Description:

DUALITY is self-contained. With eyes closed the figure is listening to music from the instrument above which psychic energy plays. In this trump of DUALITY masculine nature stands between two opposite feminine figures who represent the DUALITY of good and evil. The jackal is the nightmare shadow side in contrast to the woman's daylight beauty. Humanity has a thinking choice to make. He seems to choose the music of the spheres above in their cosmic order of balance, and obey what he hears from there, rather than listen to the voices on either side of him.

Interpreted use:

Identify yourself with all the sounds about you. Each is a part of your life.

Reversed (card received upside down):

You are standing between the heaviest of opposites. Turn deaf ears to empty yammerings.