No. While the coupon is fixed ,the income from the bond will change with the market price of the bond e.g. a bond is issued with a coupon of 5% ( fixed ) per ￡100 . If the bond price rises to ￡110 then the income will fall to 4.5% (i.e. 5/110 ). If the price falls to ￡90 then the income rises to 5.5% (i.e. 5/90 ).

Yes, usually fixed income in the investment industry refers to bonds.

Definitely no. Bonds are loans that people buy hoping they will accrue interest in 1-5 years or more. Fixed income is someone's salary.

Yes they are one and the same. Tell me dear child with your little puppy, why do you ask?