Frequency: The word is one of the 1500 most common words in English.
1.
If something is useful, you can use it to do something or to help you in some way.
The slow cooker is very useful for people who go out all day...
Hypnotherapy can be useful in helping you give up smoking...
The police gained a great deal of useful information about the organization.
? useless
ADJ
• usefully
...the problems to which computers could be usefully applied...
We need to find ways of dealing creatively and usefully with our feelings.
ADV: ADV with v
• usefulness
His interest lay in the usefulness of his work, rather than in any personal credit.
N-UNCOUNT
2.
If an object or skill comes in useful, it can help you achieve something in a particular situation.
The accommodation is some distance from the clubhouse, so a hire car comes in useful.
PHRASE: V inflects