Underpricing  Issuing securities at less than their market value.
Underwriter  An investment bank that agrees to purchase a new issue of securities from an issuer and distribute it to investors, making a profit on the fees charged for this service.
Underwriting Agreement 

The contract between a corporation issuing new publicly offered securities and the managing underwriter as agent for the underwriting group. Compare to agreement among underwriters.

Unlisted Security  A security not listed on an exchange.