Operating a cash register (ringing up sales) — the act of handling the register at stores; also used as a job description for part‑time work.
大学生のアルバイトでレジ打ちを始めた。
I started working a part‑time job as a cashier (operating the register) while at university.
忙しい時間帯はレジ打ちのミスが増えるので注意が必要だ。
During busy hours, mistakes in operating the register increase, so care is needed.
新人はまず正確な入力とお釣りの計算を学び、レジ打ちに慣れていく。
New workers first learn accurate entry and change calculation, and gradually get used to operating the register.