What is Capital Note?

Legal Definition
Capital notes are several types of securities. "Capital note" has a number of meanings, as it can be either an equity security, a debt security or a form of security used in structured finance. In all cases, the use of the term "capital" is to denote that the security is relatively junior in the issuing corporation's order of priorities in claims for its assets.
-- Wikipedia
Legal Definition
A NOTE issued by a BANK or bank holding company that can qualify as TIER 2 CAPITAL. To be included in the Tier 2 computation, the security must be structured as a NONCALLABLE BOND with an original maturity of at least 7 years, or a MANDATORY CONVERTIBLE BOND that results in conversion into the bank