Definition of effective
(Entry 1 of 2)
1a : producing a decided, decisive, or desired effect an effective policy
b : impressive, striking a gold lamé fabric studded with effective … precious stones— Stanley Marcus
2 : being in effect : operative the tax becomes effective next year
3 : actual the need to increase effective demand for goods
4 : ready for service or action
effective manpower
5 of a rate of interest : equal to the rate of simple interest that yields the same amount when the interest is paid once at the end of the interest period as a quoted rate of interest does when calculated at compound interest over the same period — compare nominal sense 4
effective
nounDefinition of effective (Entry 2 of 2)
: one that is effective (see effective entry 1) especially : a soldier equipped for duty
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Time Traveler for effective
The first known use of effective was in the 14th century
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