Achaemenian

[ ak-uh-mee-nee-uh n ]

/ ˌæk əˈmi ni ən /

of or relating to the Achaemenids or their language, as recorded in cuneiform inscriptions.

Origin of Achaemenian

1710–20; < Latin Achaemeni(us) (< Greek Achaimén(ēs) Achaemenes + Latin -ius adj. suffix) + -an

He is indeed the only monarch of the Achaemenian line who appears to have been bloodthirsty by temperament.
The Seven Great Monarchies Of The Ancient Eastern World, Vol 5. (of 7): Persia|George Rawlinson
The Saseanian reliefs need not on the whole shrink from a comparison with those of the Achaemenian Persians.
The Seven Great Monarchies Of The Ancient Eastern World, Vol 7. (of 7): The Sassanian or New Persian Empire|George Rawlinson
The Achaemenian sovereign did not hesitate to forestall the attack, and promptly assumed the offensive.
History Of Egypt, Chalda, Syria, Babylonia, and Assyria, Volume 9 (of 12)|G. Maspero
Anzan had been first occupied, it would appear, by his great-grandfather Teispes the Achaemenian.
A Primer of Assyriology|Archibald Henry Sayce