Noah Webster's New International Dictionary of the English Language

1. (adv.) With the back in advance or foremost; as, to ride backward.

2. (adv.) Toward the back; toward the rear; as, to throw the arms backward.

3. (adv.) On the back, or with the back downward.

4. (adv.) Toward, or in, past time or events; ago.

5. (adv.) By way of reflection; reflexively.

6. (adv.) From a better to a worse state, as from honor to shame, from religion to sin.

7. (adv.) In a contrary or reverse manner, way, or direction; contrarily; as, to read backwards.