The nominal or stated amount assigned to a security by the issuer. For shares, it is the original cost of the stock shown on the certificate; for bonds, it is the amount paid to the holder at maturity. Also known as par value or simply par.
For an equity share, the face value is usually a very small amount ($5, $10) and does not have much bearing on the price of the share, which may quote higher in the market, at $100 or $1000 or any other price.
For a debt security, face value is the amount repaid to the investor when the bond matures. The price at which the security trades depends on the fluctuations in the interest rates in the economy.