aevum, evum; etern-; aeternus

Forever.

Long lived or living a long time.

1. A long duration of life.
2. Etymology: from Late Latin longaevitas, "great age, long life", from Latin longaevus, "of great age", which is compounded of longus, "long", and aevum, "age".

Lexicomedy: A joust cause.

1. Of or relating to a period of time intervening between (periods designated as) ancient and modern; specifically, relating to, or characteristic of the Middle Ages. Also, of art, religion, etc.; resembling or imitative of that of the Middle Ages.
2. A person who lived in the Middle Ages; also, a person whose outlook or perspective is (regarded as) characteristic of or resembles that of the Middle Ages.

In eternal remembrance.

I will sing the mercies of the Lord forever.

A motto of Abingdon School, U.K.

1. Having existed from the beginning; in an earliest or original stage or state:: "We were able to visit what some consider the forest primeval."
2. Belonging to the first or earliest age or ages; original or ancient.
3. At or from the ancient original stages in the development of something.
4. Primitive, or arising from instinct rather than from thought: "She had a primeval urge to respond to his criticism."

Term meaning "eternal youth".

The Word of the Lord endureth forever." [As seen in I Peter 1:25, of the Bible]