ESPERUS, HESPERUS is the evening star, which pales when the sun rises and is then called Lucifer, derived from lucem ferens, "light bearing" (Cicero, De natura deorum, II.20, 53).

Boethius's description of Hesperus parallels Cicero's, Bo I, Metr 5.11-12. The moon commands the night, brought on by Esperus, the evening star, Bo II, Metr 8.7-8. Hesperus proclaims the late nights and Lucifer brings the clear day, Bo IV, Metr 6.15. [Lucifer¹]

Both forms are pronounced alike; Latin initial h was not pronounced.