Word puzzle

a multiletter word

first three letter : small measurement
last three letter : something very small in size
first four letter : something which turns big into small
last four letters : big of much smaller in size
the whole word : big quantity or amount

what's the fun word ?

ANSWER :

MILLION is the word

first three letter : small measurement : MIL ( one thousandth of an inch )
last three letter : something very small in size : ION
first four letter : something which turns big into small : MILL ( for grinding )
last four letters : big of much smaller in size : LION ( Big Cat )
the whole word : big quantity or amount : MILLION