Is reliable formal or informal?

It is neutral. You can use it in speech, school writing, and business writing.

What is the difference between reliable and trustworthy?

Reliable often describes people, things, or information that work well or can be trusted. Trustworthy is used more for people.

Can I say a reliable person?

Yes. It means the person keeps promises and does what they say.

Is reliable common in IELTS writing?

Yes. It is a useful academic word, especially for sources, data, and evidence.

← Dictionary

reliable

/rɪˈlaɪ.ə.bəl/

IELTSAcademic

adjective

A reliable person or thing can be trusted to do what is needed. It works well, stays true, or gives correct results.

She is a reliable friend.
This car is very reliable.
We need reliable information.

Adinary Nuance

Reliable is about trust and steady performance. It is stronger than practical, which means useful, and closer to trustworthy when talking about people. For things, reliable means they work well again and again, not just once.

In other languages

Vietnamese: đáng tin cậy
Spanish: fiable
Chinese: 可靠的
Japanese: 信頼できる
Korean: 믿을 수 있는

Etymology

Reliable comes from the verb rely, which entered English from Old French in the late Middle Ages. The adjective became common in English in the 1700s.

Common phrases

a reliable sourcea reliable frienda reliable carreliable information

Synonyms

trustworthy dependable consistent steady

Related words

trust depend responsible accurate safe

Frequently asked questions

Is reliable formal or informal?: It is neutral. You can use it in speech, school writing, and business writing.
What is the difference between reliable and trustworthy?: Reliable often describes people, things, or information that work well or can be trusted. Trustworthy is used more for people.
Can I say a reliable person?: Yes. It means the person keeps promises and does what they say.
Is reliable common in IELTS writing?: Yes. It is a useful academic word, especially for sources, data, and evidence.