B1[C or U]physical or mental activity needed to achieve something: [+ to infinitive]If we could all make an effort to keep this office tidier it would help.You can't expect to have any friends if you don't make any effort with people.In their efforts to reduce crime the government expanded the police force.He's jogging round the park every morning in an effort to get fit for the football season.It takes a long time to prepare the dish but the results are so good that it's worth the effort.Effort and expending energyTrying and making an effort›[C]the result of an attempt to produce something, especially when its quality is low or uncertain: Do you want to have a look at his exam paper? It's a fairly poor effort.Trying and making an effortEffort and expending energybe an effortC2to be difficult, tiring, or boring to do: I'm exhausted all the time, and everything is a real effort.