What is the origin of stentorian?

Stentorian, “extremely loud; having a powerful voice,” comes from Greek Sténtōr (inflectional stem Sténtor-), the name of a Greek (more properly Achaean) warrior who fought at Troy. Stentor is mentioned in the Iliad only once, in book 5, where Hera “took the likeness of great-hearted Stentor of the brazen voice, whose voice is as the voice of fifty other men” to scold the Achaeans. According to a scholium (an ancient comment or annotation on a Greek or Latin text) on this line in the Iliad, Stentor, like several other Greek heroes who came to similar bad ends, challenged the god Hermes to a shouting contest and was killed for his impudence. Sténtōr is a Greek derivative of the Proto-Indo-European root (s)ten-, (s)ton– “to groan” (thus the literal meaning of Sténtōr is “groaner, moaner” from the verb sténein “to moan, groan, lament”). The root appears in Sanskrit as stánati “(it, he) groans, thunders,” Old English stenan “to groan loudly; roar,” and Russian stonát’ “to groan.” The form without the initial s– (i.e. ten-, ton-) appears in Aeolic Greek (the dialect of the lyric poets Sappho and Alcaeus) as ténnei “(it, he) thunders,” Latin tonāre “to thunder, roar,” Old English thunor (English thunder), and Old Norse Thōrr “Thor” (the deity, literally, “thunder”). Stentorian entered English in the early 17th century.