"Strepitant" (and the related "
strepitous") are adjectives meaning
boisterous or very
noisy. Both come from the
Latin "strepitantem," present participle of "strepitare," from "strepere" (to make noise). The
Oxford English Dictionary records strepitant being used in
1842 and
1861, with "strepitantly" as late as
1913, but the vast majority of the
Google results in a search for the word turn up Latin documents, so it's certainly an obscure term in
English. (Though a
1915 letter at http://www.ku.edu/~libsite/wwi-www/Chapin/Chapin04.htm seems to use "strepitant" without having yet made it into the
OED.) Perhaps the most common English usage is in quoting this poem:
"Three makes rejoinder, expansive, explosive;
Four overbears them all, strident and strepitant"
Robert Browning, "Master Hugues of Saxe-Gotha,'
Dramatic Lyrics, 1842.
Sources:
http://wordsmith.org/awad/archives/1002
http://www.oed.com