It's an extremely effective cure for a headache.
Longman Dictionary of Contemporary English
effective
ef‧fec‧tive S2 W1 /ɪˈfektɪv/ adjective
[Word Family: noun: effect, effectiveness ≠ ineffectiveness; adjective: effective ≠ ineffective, effectual ≠ ineffectual; verb: effect; adverb: effectively ≠ ineffectively]
1. successful, and working in the way that was intended OPP ineffective:
• The cheaper drugs are just as effective in treating arthritis.
• the painting’s highly effective use of colour
• Training is often much less effective than expected.
• the most effective ways of reducing inner city congestion
REGISTER
In everyday English, people usually say that something works (well), rather than say that it is effective:
▪ • The cheaper drugs work just as well.
2. [no comparative, not before noun] if a law, agreement, or system becomes effective, it officially starts
effective from
• The cut in interest rates is effective from Monday.
3. [no comparative, only before noun] real rather than what is officially intended or generally believed:
• The rebels are in effective control of the city.
—effectiveness noun [uncountable]
• • •
COLLOCATIONS
■ adverbs
▪ extremely/highly effective • The company launched a highly effective advertising campaign.
■ nouns
▪ an effective way • What’s the most effective way to control crime?
▪ an effective method • Exams are not the most effective method of assessing students’ abilities.
▪ an effective means • Is reducing the speed limit an effective means of reducing accidents?
▪ effective action • The police must take effective action to protect the public.
▪ an effective solution • The most effective solution to traffic congestion is to build more roads.
▪ an effective treatment • Antibiotics are still the most effective treatment for this disease.
▪ an effective system • The country has a simple but effective welfare system.
• • •
THESAURUS
▪ successful achieving what you wanted, or having the effect or result you intended: • He applied for a visa three times and in the end he was successful. | • The treatment was successful. | • It was a highly successful campaign.
▪ effective having the effect or result that was wanted - used especially about treatments, drugs, or methods: • The drug is effective against a range of diseases. | • We still haven't found an effective way to solve the problem.
▪ victorious successful as a result of winning in a game, election, war etc: • the captain of the victorious team | • She emerged victorious in the second round of voting.
▪ promising likely to be very successful in the future, used especially about someone who is good at a job, sport, art etc: • a promising young athlete | • He gave up a promising career in banking.
▪ thriving very successful – used about a company, industry, or organization that is doing well at a particular time: • The area has a thriving tourist industry. | • The school is thriving academically.
▪ booming extremely successful – used about an economy, or when business or trade is increasing: • the booming economy in China | • Business is booming.
Oxford Advanced Learner's Dictionary
effective
ef·fect·ive [ɪˈfektɪv] [ɪˈfektɪv] adjective
1. producing the result that is wanted or intended; producing a successful result
• Long prison sentences can be a very effective deterrent for offenders.
• Aspirin is a simple but highly effective treatment.
• drugs that are effective against cancer
• Some people believe that violence is an effective way of protesting.
• I admire the effective use of colour in her paintings.
Opp: ineffective
see also cost-effective
2. only before noun in reality, although not officially intended
• the effective, if not the actual, leader of the party
• In spite of what they are told, parents have no effective choice of schools.
• He has now taken effective control of the country.
3. (formal) (of laws and rules) coming into use
• The new speed limit on this road becomes effective from 1 June.
Derived Word: effectiveness
See also: effectivity
Word Origin:
late Middle English: from Latin effectivus, from efficere ‘accomplish’, from ex- ‘out, thoroughly’ + facere ‘do, make’.
Thesaurus:
effective [effective effectiveness] adj.
• a simple but highly effective treatment
successful • • powerful •
Opp: ineffective
effective/successful/powerful in sth
effective/successful/powerful in doing sth
an effective/successful/powerful campaign/challenge
Example Bank:
• The drug is generally effective in reducing pain.
• This method is effective enough with greenfly.
• We find advertising on the radio very effective.
• What makes a TV programme politically effective?
• a highly effective technique
• directly effective treaty provisions
• effective at keeping out the wind
• effective in helping people to stop smoking
• He argued that long prison sentences could be a very effective deterrent for offenders.
Cambridge Advanced Learner's Dictionary
effect
effect (USE) /ɪˈfekt/
noun [U]
use:
The present system of payment will remain in effect (= be used) until the end of the rental agreement.
When do the new driving laws come into effect?
The new salary increases will take effect (= begin) from January onwards.
effective /ɪˈfek.tɪv/
adjective
The new laws will become effective next month.
See also effective at effect (RESULT).
x
effect (RESULT) /ɪˈfekt/
noun [C or U]
1 the result of a particular influence:
The radiation leak has had a disastrous effect on/upon the environment.
I tried taking tablets for the headache but they didn't have any effect.
I think I'm suffering from the effects of too little sleep.
She has a lot of confidence which she uses to good effect (= to her advantage) in interviews.
See also after effects.
2 take effect to produce or achieve the results you want:
They had to wait ten minutes for the anaesthetic to take effect before they stitched up the cut.
3 MAINLY DISAPPROVING for effect If you say or do something for effect, you intentionally do it to shock people or attract their attention:
I get the impression that she uses bad language in meetings for effect.
4 in effect in fact, or in practice:
So in effect the government have lowered taxes for the rich and raised them for the poor.
See also effect (USE). effective /ɪˈfek.tɪv/
adjective
1 successful or achieving the results that you want:
It's an extremely effective cure for a headache.
The lighting for the production made a very effective use of shadow.
She's a very effective teacher.
NOTE: The opposite is ineffective.
2 [before noun] in fact, although not officially:
Although she's not officially our boss, she's in effective control of the office.
See also effective at effect (USE).
effectively /ɪˈfek.tɪv.li/
adverb
1 in a way that is successful and achieves what you want:
The tablets work more effectively if you take a hot drink after them.
2 used when you describe what the real result of a situation is:
His wife left him when the children were small, so he effectively brought up the family himself.
Effectively, we have to start again from scratch.
effectiveness /ɪˈfek.tɪv.nəs/
noun [U]
There are doubts about the effectiveness of the new drug (= how successful it is) in treating the disease.
effectual /ɪˈfek.tju.əl/
adjective FORMAL
effective and successful:
They wish to promote a real and effectual understanding between the two countries.
effectually /ɪˈfek.tju.əl.i/
adverb FORMAL