Which one is NOT a palm orientation use in American sign language

-forward
-backward
- horizontal
- palm toward palm

To determine which one is NOT a palm orientation used in American Sign Language (ASL), we can understand the palm orientations in ASL and then identify the one that does not fit.

Palm orientations in ASL refer to the direction in which the palm of the hand faces while signing. There are four main palm orientations used in ASL:

1. Forward: This palm orientation has the palm facing forward, away from the signer's body. It is commonly used for signs involving pointing or indicating objects or locations.

2. Backward: This palm orientation has the back of the hand facing forward, away from the signer's body. It is used for signs related to describing or indicating the back side of something.

3. Horizontal: This palm orientation has the palm facing down or up, horizontally to the ground. It is used for signs that involve describing or indicating something flat or level.

4. Palm toward palm: This palm orientation has both palms facing each other. It is commonly used for signs that involve holding or showing an object between the palms, such as signing "book" or "bathroom".

Now, looking at the options provided:
- Forward: This is a valid palm orientation in ASL.
- Backward: This is also a valid palm orientation in ASL.
- Horizontal: This is also a valid palm orientation in ASL.
- Palm toward palm: This is a valid palm orientation in ASL.

Therefore, the answer is that all the given options represent valid palm orientations in American Sign Language, so none of them is NOT a palm orientation in ASL.