a. 同时代的

[医] 同年龄的

[ adj ]
of the same period
<adj.all>

Coetaneous \Co`e*ta"ne*ous\, a. [L. coaetaneus; co- + aetas
age.]
Of the same age; beginning to exist at the same time;
contemporaneous. -- {Co`e*ta"ne*ous*ly}, adv.

And all [members of the body] are coetaneous.
--Bentley.