Synonyms for Ear-piercing:

adj.

deafening (adjective)
screaming.
loud (adjective)
strident, raucous, piercing.
raucous (adjective)
grating, jarring, hoarse, rasping, acute, harsh.
shrill (adjective)
shrill, creaky, treble, cutting, harsh, high-pitched, hoarse, rasping, grating, scraping, reedy, squeaky, scratching, screaming, screeching, shrieking, whistling, squealing, penetrating, piercing, Caterwauling, whining, acute, jangling, raucous, jarring, strident.

Other synonyms:

adj.
piercing, screaming, raucous, shrill.