A bond issued by a company that can be exchanged for shares of a different company, typically a subsidiary or affiliate. Used in finance contexts.
The company issued exchangeable bonds that are exchangeable for shares of its subsidiary.
転換社債 (convertible bond) is exchanged for shares of the issuing company itself, while 他社株転換社債 is exchanged for shares of a different company.
Compound of 他社 (other company), 株 (stock), 転換 (conversion), and 社債 (corporate bond). The term is a direct description of the financial instrument.