I couldn’t give a better answer then the above but heres Bob Marley for you. Redemption song. In this context theirs a meaning of deliverance, emancipation, rescue, or salvation,

Old pirates, yes, they rob I;

Sold I to the merchant ships,

Minutes after they took I

From the bottomless pit.

But my hand was made strong

By the hand of the Almighty.

We forward in this generation

Triumphantly.

Won’t you help to sing

another songs of freedom

‘Cause all I ever have:

Redemption songs;

Redemption songs.

Emancipate yourselves from mental slavery;

None but ourselves can free our minds.

Have no fear for atomic energy,

‘Cause none of them can stop the time.

How long shall they kill our prophets,

While we stand aside and look? Ooh!

Some say it’s just a part of it:

We’ve got to fullfil the book.

Won’t you help to sing

This songs of freedom-

‘Cause all I ever have:

Redemption songs;

Redemption songs;

Redemption songs.

Emancipate yourselves from mental slavery;

None but ourselves can free our mind.

Wo! Have no fear for atomic energy,

‘Cause none of them-a can-a stop-a the time.

How long shall they kill our prophets,

While we stand aside and look?

Yes, some say it’s just a part of it:

We’ve got to fullfil the book.

Won’t you have to sing

This songs of freedom? –

‘Cause all I ever had:

Redemption songs –

All I ever had:

Redemption songs:

These songs of freedom,

Songs of freedom.

That just shows the futility of defining a word with itself or its derivatives. Aside from redeeming all your food coupons (I think they can be redeemed for 1/20 of one cent or something like that), I think you’re more concerned with the more metaphorical meaning of redemption, which is something close to salvation. In a way, it is the same meaning, that is, at redemption somebody’s real worth is finally realized (like those food coupons). A criminal can meet redemption by becoming a good samaritan. A terrorist might be redeemed by saving a city (huh? well, I’m having trouble with the whole concept of salvation, but you get it, I’m sure). I’ve got it. A Republican could be redeemed by becoming a Democrat, or at least by understanding what working people are like. Does that make it easier?

Back in the old days you could redeem a debt – that meant paying it back. So if you pawned your coat because you needed some cash for a while, when you had some spare cash you could go and redeem your coat.

The Christian sense of the word is similar if you think about it – people owe God a debt they can’t pay (because nobody is perfect) so God redeemed them himself via Christ.

The other explanations above make sense in this light I think.

– (Christianity) the act of delivering from sin or saving from evil

– repayment of the principal amount of a debt or security at or before maturity (as when a corporation repurchases its own stock)

– the act of purchasing back something previously sold

To make right you sins / misdeeds. See Atonement.