pin /pɪn/ verb [T] (present participle pinning, past tense and past participle pinned)
› to fasten something with a pin: We're not allowed to pin anything on these walls. She had a red ribbon pinned to her collar.
pin sb to/against/under, etc › to force someone to stay in a position by holding them: They pinned him to the ground. → See also pin your hopes on sb/sth