#602 - AIÓN – AIÓNIOS – ("shown to denote limited duration") John Wesley Hanson http://www.tentmaker.org/books/Aion_lim.html
"THE VOCABULARY OF THE GREEK TESTAMENT (edited by James Hope Moulton and George Milligan) is helpful. Concerning aionios we read, "In general, the word depicts that of which the horizon is not in view . . ." (p.16). If the horizon of the extermination spoken of by Paul in 2 Thessalonians 1:9 is simply not in view, then we can see that what Paul says in 1 Corinthians 15:22 can truly occur. The same all who are dying in Adam, which includes some who incur eonian extermination, can indeed eventually be vivified in Christ.
The Bible, in fact, does not speak of judgment and condemnation, death and destruction, hades and Gehenna, or any of these serious consequences of sin, as unending. It may refer to them as not having the end in view, but none of these fearful works of God can keep Him from achieving His will (1Tim.2:4); reconciling all through the blood of Christ's cross (Col.1:20, and becoming All in all (1 Cor.15:28)."