1) debenture is a type of debt instrument that is not 
secured by physical asset.
2) bond is a debt investment in which investor loans money 
to an company that borrows the funds for a defined period 
of time at a fixed interest rate.

Bonds is a debt instrument which are issued at discount and 
redeemed after a fixed period of time as it is generally 
issued by government. 



Debentures is also a debt instrument but unsecured as it is 
issued by corporates whers no colateral is made against 
this instrument.

Not much only different terminology.
still a few difference can be found out
(a) bonds are issued by govt or govt agencies whereas 
Debentures are issued by corporate entities
(b) bonds are not secured by assets but debentures in India 
are secured by assets.

In most financial markets the terms Bonds and debentures 
are used interchangably. They both serve the same purpose.

Bonds:Long-term debt securities issued by the Government of 
India or any of the State Government’s or undertakings 
owned by them or by development financial institutions are 
called as bonds. 

Debentures: Instruments issued by other entities are called 
debentures.

A> Bond is issued by govt. bodies or semi govt. like-- 
ioc,public sector banks, state govt,
 Debenture can not be issued by govt. this is issued by 
corporate houses
B> In the most aspect the both are relatively in the 
nature.

Bonds are issued by Government,municipalities,PSUs,companies
Debentures are issued by Private Company.

Bonds are not mortgage befor maturity period.
Debentures are mortgage before maturity period.