stri·dent 
(strīdnt)
(strīdnt)adj.
1. Loud, harsh, grating, or shrill: a strident voice. See Synonyms at vociferous.
2. Forcefully assertive or severely critical: strident rhetoric.
[Latin strīdēns, strīdent-, present participle of strīdēre, to make harsh sounds, ultimately of imitative origin.]
stridence, striden·cy n.
strident·ly adv.