effective

[ ih-fek-tiv, ee-fek‐ ]

adjective

1. adequate to accomplish a purpose; producing the intended or expected result:

   effective teaching methods; effective steps toward peace.

   Synonyms: competent, capable

   Antonyms: useless, futile

2. actually in operation or in force; functioning:

   The law becomes effective at midnight.

3. producing a deep or vivid impression; striking:

   an effective photograph.

4. prepared and available for service, especially military service.

noun

1. a member of the armed forces fit for duty or active service.
2. the effective total of a military force.

effective

/ ɪˈfɛktɪv /

adjective

1. productive of or capable of producing a result
2. in effect; operative

   effective from midnight

3. producing a striking impression; impressive

   an effective entrance

4. prenominal actual rather than theoretical; real

   the effective income after deductions

5. (of a military force, etc) equipped and prepared for action
6. physics (of an alternating quantity) having a value that is the square root of the mean of the squares of the magnitude measured at each instant over a defined period of time, usually one cycle See also root mean square

noun

1. a serviceman who is equipped and prepared for action

Derived Forms

• efˈfectiveness, noun
• efˈfectively, adverb

Other Words From

• ef·fec·tive·ly adverb
• ef·fec·tive·ness ef·fec·tiv·i·ty [ih-fek-, tiv, -i-tee, ee-fek-] noun
• pre·ef·fec·tive adjective
• qua·si-ef·fec·tive adjective
• sub·ef·fec·tive adjective
• su·per·ef·fec·tive adjective
• un·ef·fec·tive adjective

Word History and Origins

Origin of effective¹

First recorded in 1350–1400; Middle English from Latin effectīvus “practical,” equivalent to effect(us), past participle of efficere ( effect ) + -īvus adjective suffix ( -ive )

Synonym Study

operative. telling.

Example Sentences

By using genetic evidence to recount the shared history of people and plants, the study brings wider appreciation to the effective methods Indigenous peoples used to manage the land for millennia.

From Science Daily

Maddipati believes that looking at acute inflammation and chronic inflammation as having two separate causes could lead to vastly different, and potentially more effective, treatments for a variety of diseases, including cancer.

From Science Daily

"Non-steroidal anti-inflammatory drugs, or NSAIDs, may not be as effective with chronic inflammation like they are with acute inflammation," said Maddipati.

From Science Daily

As climate change accelerates the frequency and severity of storms, the need for effective coastal defenses has become increasingly urgent.

From Science Daily

However, the center's study reveals that natural ecosystems -- particularly mangroves -- can be equally, if not more, effective as coastal defenses, while providing additional environmental benefits.

From Science Daily

Related Words

• active
• adequate
• compelling
• competent
• direct
• efficient
• forceful
• impressive
• potent
• powerful
• practical
• successful
• useful
• valid