What does the word 'destroyed' mean in the phrase 'the body of sin might be destroyed'?

In the Greek, the term rendered 'destroyed' does not mean removed or annihilated; it means knocked out of commission. The body of sin, identified as old Adam, has lost its power and should no longer be served, though it is not eliminated.

Les explains that this identification is by faith: when Christ hung on the cross, He died our death, and God saw us in Him; in the tomb and in resurrection, God saw us in Him. Les substitutes 'old Adam' for the word 'sin,' so the body of sin is the old Adam crucified with Him. Going back to the Greek, 'destroyed' does not mean removed and annihilated; it means knocked out of commission, having lost its power. Les illustrates it with a main fuse box: pulling the lever turns lights off, but the power is still there and can be flipped back on. That is what happened to old Adam—he has lost his power, so we should not serve him; the unbeliever, by contrast, lives to satisfy old Adam's desires.

What does 'destroyed' mean when the Bible says the body of sin is destroyed?

Destroyed in that phrase does not mean removed or annihilated. In the Greek it means knocked out of commission; the body of sin, or old Adam, has lost its power. It is like a main fuse pulled: lights go out, but power remains and can be restored. Believers should no longer serve old Adam.