punishment by cutting off ears
刵 refers specifically to an ancient punishment of cutting off a person's ears. It is a rare, narrow term with no extended or abstract meanings.
刵 combines 耳 (ear) and 刂 (knife), directly depicting the act of cutting off an ear as a punishment.
A knife 刂 beside an ear 耳: the punishment is cutting off ears.
For ジ, imagine the ear-cutting punishment being carried out by a judge who pronounces the sentence with a sharp 'Gee!' — the sound of the judge's exclamation cues ジ.