• 握手あくしゅ — handshake
• 握力あくりょく — grip strength
• 把握はあく — understanding / grasp
• 掌握しょうあく — grasp (of power, control)
• 握りにぎり — grip / also used for nigiri sushi
• 握にぎり拳こぶし — clenched fist
• 握にぎる — to grasp / to hold

握 combines 扌 (hand/action) with 屋 (phonetic アク). It depicts the act of firmly taking something in the hand, extending to abstract ideas like 把握 (grasping concepts).

彼かれは 私わたしの 手てを 強つよく 握にぎった。
He held my hand tightly.

彼女かのじょは 権力けんりょくを 握にぎっている。
She holds the power.