effective
2 ENTRIES FOUND:
Britannica Dictionary definition of EFFECTIVE
1
[more effective; most effective]
:
producing a result that is wanted
:
having an intended effect
—
opposite ineffective
-
drugs effective in the treatment of a disease = drugs effective in treating a disease = drugs effective against a disease
-
It's a simple but effective technique.
-
He gave an effective speech.
2
of a law, rule, etc.
:
in use
:
active
-
The law becomes effective [=the law takes effect; the law will start to be used] next year.
-
the effective date of the law [=the day when the law starts to be used]
3
:
starting at a particular time
— used to introduce a clause
-
Effective [=starting, as of] tomorrow, the store will be open until 8:00 p.m. every day.
-
Effective next month, the landfill will no longer accept old televisions.
4
always used before a noun
— used to describe something that exists or has an effect but that is not officially stated or recognized
-
the effective tax rate
-
The army has taken effective control of the city.
— effectiveness
noun [noncount]-
The effectiveness of the drug was questioned.
