It takes more than Neptunes spear to be loud and grating (8)
I believe the answer is:
strident
'loud and grating' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for strident that I've seen before include "Clamorous" , "harsh noise" , "(Of a voice) loud and grating" , "Loud and harsh over tridents" , "ear-piercing" .)