甚 — tremendously, very, great, exceedingly

それは甚だしい偏見です。

That is an extreme prejudice.

文句もんくを 言いうなんて 失礼しつれいも 甚はなはだしい

It is outrageous of them to complain.

夜中よなかに 電話でんわがかかってくるのは甚はなはだ 迷惑めいわくだ

It is very annoying when someone calls in the middle of the night.