What is the difference between Tate of reaction and rate of disappearence of one reactant

@ satheesh 
what u need to understand is that , suppose you are doing a reaction . 
so, u must have some reactant initially , and after some period of time the reactant will going to form product under suitable condition , and that is what we called as reaction . ryt ?? 
and so, during a reaction , the reactant will obviously decrease in concentration , and the product will also increase in concentration , that is same as rate of reaction . "
RATE OF REACTION BESICALLY MEANS , THE SPEED OR THE RATE AT WHICH THE REACTANT WILL CONSUME , AND THE PRODUCT WILL FORM . 
SO, RATE OF DISAPPEARANCE OF REACTANT AND RATE OF REACTION , ARE BOTH SAME . 
hope it clears your doubt 
all the best ..

For expressing the rate of a reaction where stoichiometric coefficients of reactant or products are not equal to one,rate of disappearance of any of the reactants or the rate of appearance of products is divided by their respective stoichiometric coefficients for eg

2HI------->H2+I2

RATE=(-1\2)∆HI/∆t =∆H2/∆t=∆I2/∆t