Stroke count: 12
Meaning: surprised, frightened
Kunyomi: おどろ.く
Onyomi: ガク
Composition: 忄 咢
Radical: 心
Meaning: heart
愕然 (ガクゼン) astonished, shocked, amazed, astounded, aghast
驚く (おどろく) to be surprised, to be astonished