clench

verb
1
when you clench your hands, teeth, etc., or when they clench, you press them together tightly, usually showing that you are angry, determined or upset
فشردن, محکم گرفتن
2
to hold something tightly
محکم گرفتن, فشردن
Her pen was clenched between her teeth.
She had a gun clenched tightly in her hand.
He clenched the steering wheel tightly.