Modesty
Humility
noun, な adjective
The modesty void is that big pit you go into when you are showing modesty or humility.
けんきょ
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
その謙虚な男性が実はマフィアの一員だったなんて、信じられません。
I can’t believe that humble man was actually a member of the mafia.