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bond; bill; certificate; security
証券会社に口座を開いた。
Opened an account at a securities firm.
国債は安全性の高い証券とされる。
Government bonds are considered high-safety securities.
株式市場で証券を売買するには証券口座が必要だ。
To buy and sell securities on the stock market, you need a brokerage account.