Verbs

(v)close up, clam up, dummy up, shut up, belt up, button up, be quiet, keep mumrefuse to talk or stop talking; fall silent“The children shut up when their father approached”
(v)lock in, lock away, lock, put away, shut up, shut away, lock upplace in a place where something cannot be removed or someone cannot escape“The parents locked her daughter up for the weekend”, “She locked her jewels in the safe”
(v)hush, quieten, silence, still, shut up, hush upcause to be quiet or not talk“Please silence the children in the church!”

Adjectives

(s)pent, shut upclosely confined