Is masturbation to be considered a sin?

The Bible never explicitly mentions masturbation or states whether or not masturbation is a sin. The Scripture most frequently pointed to in regards to masturbation is the story of Onan in Genesis 38:9-10. Some interpret this passage as saying that “spilling your seed” on the ground is a sin.

So on Morning Teaser today, we ask if masturbation is considered a sin?