(noun, adjective)


1. producing or capable of producing an intended result or having a striking effect

- an air-cooled motor was more effective than a witch's broomstick for rapid long-distance transportation

- effective teaching methods

- effective steps toward peace

Similar word(s): trenchant, impelling, impressive, telling, efficacious, efficient, potent, stiff, strong, powerful, useful, utile, effectual, efficacious

2. able to accomplish a purpose; functioning effectively

- people who will do nothing unless they get something out of it for themselves are often highly effective persons...

- effective personnel

Similar word(s): competent, efficient

3. works well as a means or remedy

- an effective reprimand

- a lotion that is effective in cases of prickly heat

Similar word(s): efficacious

4. exerting force or influence

- the law is effective immediately

- the law is already in effect (or in force)

Similar word(s): operative, good

5. existing in fact; not theoretical; real

- a decline in the effective demand

- confused increased equipment and expenditure with the quantity of effective work done

Similar word(s): actual, existent

6. ready for service

- the fort was held by about 100 effective soldiers

Similar word(s): operational

Sentences with effective as an adjective:

- The pill is an effective method of birth control.

- The president delivered an effective speech!

- How long does it take to make a bunch of civilians an effective military force?

- My effective income after taxes and child support is $500 a month.

- The effective radiated power is determined by multiplying the transmitter power output with the antenna gain.

- The effective voltage of an alternating current is 0.7 times its peak voltage.

- The curfew is effective at midnight.


1. (military) A soldier fit for duty.