Oriented toward the back.

"The battleship had three backwards guns at the stern, in addition to the primary complement."

Reversed.

"The backwards lettering on emergency vehicles makes it possible to read in the rear-view mirror."

Behind current trends or technology.

"Modern medicine regards the use of leeches as a backwards practice."

Clumsy, inept, or inefficient, especially in learning.

"He was a very backwards scholar, but he was a marvel on the football field."

Toward the back.

"Life is lived forwards, but understood backwards.—Søren Kierkegaard"

In the opposite direction to usual.

"The clock did not work because the battery was inserted backwards."

In a manner such that the back precedes the front.

"The tour guide walked backwards while droning on to the bored seniors."

Towards the past; ago