co·e·val 
(kō-ēvəl)
(kō-ēvəl)adj.
Originating or existing during the same period; lasting through the same era.
n.
One of the same era or period; a contemporary.
[From Late Latin coaevus : co-, co- + aevum, age; see aiw- in the Appendix of Indo-European roots.]
co·eval·ly adv.