Greek root (‘ktizo’ ktid-zo) is related to the act of creating and its creator; in this sense meaning God the Creator of all things. Paul is speaking of the first creating of all things by our LORD. The "creature", or 'original formation' of all things, also awaits the future time of God's Eternity with the manifesting of the sons of God. That means God's creation also waits for the future new heavens and a new earth time.
     Some might say at this point, "Well, what does that have to do with the idea of a first earth age?" Hold on, Paul's getting ready to show us in the next verses.

Rom 8:20    For the creature was made subject to vanity, not willingly, but by reason of Him Who hath subjected the same in hope,
21  Because the creature itself also shall be delivered from the bondage of corruption into the glorious liberty of the children of God.

     Note what Paul says here, that the "creature" was "made subject to vanity". Do you recall the 'tohuw va bohuw' Hebrew phrase of Genesis 1:2 translated to "without form, and void"? We learned in the first Genesis study that tohuw va bohuw phrase really means the earth was in a waste and undistinguishable ruin state. That Hebrew word 'tohuw' was also translated to "in vain" where God said He did not create the earth "in vain", meaning in a state of vanity.

 

 Isaiah 45:18. For thus saith the Lord That created the heavens; God himself that formed the earth and made it; He hath established it, He created it not in vain, He formed it to be inhabited: I am the Lord.

 

This Greek word for "vanity" Paul used is in that same idea about the "creature". But is that what Paul is really talking about here?
     Paul made this very plain, because note he says the "creature" was placed in a state of vanity, or in vain, meaning in a state of "bondage of corruption" even. Not only does Paul say the creation was made subject to vanity, but also that it will one day be delivered from the state of corruption it's been in.
     Here's where we have to ponder this for a while. Something that is put into subjection to corruption and bondage naturally was not always in that state. Even without going into the Greek one should understand that's what Paul is saying with this kind of comparison of conditions or states. He is speaking of the condition that God's creation is in today with that vanity and bondage of corruption idea, because this time(age) we are now in, has been "kept in store, reserved unto fire against the day of judgment" like Peter said.

 

 2 Pet 3:7. But the heavens and the earth which are now, by the same word are kept in store, reserved unto fire against the day of judgement and perdition of ungodly men.

 

Thus, the state God's creation is in today is one of decay, an imperfect condition, and not how God originally created it. If we think His creation today is beautiful, then wait; for we haven't seen anything yet when He will put it back to its original Perfect state.
       
Rom 8:22    For we know that the whole creation groaneth and travaileth in pain together until now.

Here we have it; the KJV translators finally translated that Greek word 'ktisis' as "creation". All of God's creation today for this second earth age groans and travails in pain for release from the state of bondage and corruption it's been in. Even "until now", meaning to this day, the whole creation groans for that release by God to the new heavens and a new earth.

     Rom 8:23   And not only they, but ourselves also, which have the firstfruits of the Spirit, even we