ef ‧ fec ‧ tive S2 W1 /ɪˈfektɪv/ BrE AmE 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
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
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]
• • •
▪ extremely/highly effective
The company launched a highly effective advertising campaign.
▪ 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.
• • •
▪ 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.