Greek word · Strong's G166

αἰώνιος

aiṓnios · adjective · “eternal, everlasting”

In a sentence

Aiōnios means eternal — the adjective behind “eternal life” and “everlasting.” It describes both the unending duration and the divine quality of life with God.

Aiōnios is the adjective for the age (aiōn) to come — and so for what belongs to that age: God himself, the life he gives, the home he prepares.

“Eternal life” (zōē aiōnios) is not just life of endless length; it is life of the coming age, already begun in Christ. Wherever Scripture says aiōnios — life, kingdom, redemption — it points to God’s unending good.

Strong's reference

Definition: perpetual (also used of past time, or past and future as well)

KJV usage: eternal, for ever, everlasting, world (began)

Reference gloss from Strong's Concordance (1890, public domain).

Key verses BSB · Public Domain (CC0)

John 3:16 “For God so loved the world that He gave His one and only Son, that everyone who believes in Him shall not perish but have eternal life.” Romans 6:23 “For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord.” 2 Corinthians 4:17 “For our light and momentary affliction is producing for us an eternal weight of glory that is far beyond comparison.”

Original BibleDawn word study. Original-language data and the public-domain Strong's (1890) gloss are referenced; see sources.