From Longman Dictionary of Contemporary Englishusefuluse‧ful /ˈjuːsfəl/ ●●●S1W1 adjectiveUSEFULhelping you to do or get what you want opp uselessuseful informationA little Japanese can be really useful.useful forThe space under the desk is useful for storing CDs.useful totechniques that could be useful to teachersCan you come and make yourself useful (=help people to do something)? —usefully adverbCOLLOCATIONSnounsuseful information/adviceShe gave me some useful advice.a useful tipTheir website has some useful tips on selling your home.a useful way of doing somethingKeeping lists of the words you learn is a useful way of remembering vocabulary.a useful toolThe Internet is a useful tool for investors.a useful contributionHe played well and made a useful contribution to the team’s performance.verbsfind something usefulDid you find the book useful?prove useful formal (=be useful)This equipment could prove useful in testing babies’ hearing.phrasesit is useful to do somethingIt is useful to practise in front of an audience.come in useful (=be useful)The extra income would come in useful.make yourself useful (=be helpful)Don’t just stand there – make yourself useful!serve a useful purpose/function (=be useful)Sending her to prison would serve no useful purpose.THESAURUSuseful something that is useful makes it easier for you to do somethingHe gave me some useful advice.a useful thing to knowhandy informal useful – used especially about something that is convenient and easy to usea handy little bookletThe book is full of handy hints.I always keep old jars – you never know when they might come in handy (=be useful).helpful useful because it helps you to do somethingThis drug can be helpful in treating depression.helpful advicehelpful suggestionsof use [not before noun] if someone or something is of use, they are useful for you when you are doing somethingI hope you’ll find the book of use.He wants to be of use.worthwhile if doing something is worthwhile, it is useful for you and you benefit from doing itThe training was certainly worthwhile.a worthwhile experience It is worthwhile to start by asking ourselves why people get involved in crime. very usefulvaluable very useful in helping you do somethingHis information was very valuable to the police.The course was a valuable experience for me.a valuable contributioninvaluable extremely useful in helping you do somethingHis help was invaluable.The drug could be invaluable for treating cancer patients. an invaluable experienceindispensable someone or something that is indispensable is so useful and important that you cannot do something without themFor walkers, a good compass is indispensable.He became an indispensable part of the team. an indispensable guide to travelling in Italybe great for something informal to be very useful for doing somethingThe bag is great for taking on holiday.