Synonyms for Strident (same or very similar meaning)
WordNet sense 1 (conspicuously and offensively loud; given to vehement outcry):
blatant, clamorous, vociferous, clamant
WordNet sense 2 (full of or characterized by loud and nonmusical sounds):
noisy
WordNet sense 3 (of speech sounds produced by forcing air through a constricted passage (as `f', `s', `z', or `th' in both `thin' and `then')):
fricative, sibilant, continuant, spirant
WordNet sense 4 ((of speech sounds); produced with the back of the tongue raised toward the hard palate; characterized by a hissing or hushing sound (as `s' and `sh')):
soft
WordNet sense 5 (being sharply insistent on being heard):
shrill
WordNet sense 6 (requiring attention or action):
imperative
WordNet sense 7 (unpleasantly loud and harsh):
raucous
WordNet sense 8 (having an unpleasant sound):
cacophonic
From the ODE community, based on WordNet
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