Lengthy vs Long

When to use each in English, with meaning, register, and examples.

Lengthy

Top 1,000 (very common)C1adjective

Long

Top 1,000 (very common)
 LengthyLong
Pronunciation🇬🇧 /["/ˈleŋkθi/"]/🇺🇸 /["/ˈleŋkθi/"]/🇬🇧 //lɒŋ//🇺🇸 //lɔːŋ//
Meaningvery long; taking a lot of time or spaceSomething that has a big distance from one end to another.
Examplelengthy delaysThe meeting felt very long.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 1,000 (very common)
CEFR levelC1-
Part of speechadjective
Collocationsbe, extremely, fairly, verylong distance, long time, long journey, long list
Antonymsbrief, short, conciseshort, brief
Common mistakesConfused with 'long' which can describe physical length, while 'lengthy' describes duration or detail., Used inappropriately for short items, where a term like 'brief' would be better., Assuming 'lengthy' can describe anything; usually it pertains to processes or texts.Confusing 'long' with 'tall' when referring to height., Using 'long' incorrectly to describe time when a specific duration is needed.
Usage notesUse 'lengthy' to describe something that is longer than usual, such as a speech or a document. It is suitable for both written and spoken language but may come off as slightly formal in casual conversations.Use ‘long’ to describe physical length or duration. Avoid when discussing smallness or brevity.

See it in real clips

Long

Frequently asked questions: Lengthy vs Long

What's the difference between Lengthy and Long?

Lengthy: very long; taking a lot of time or space Long: Something that has a big distance from one end to another.

Can you show an example of each?

Lengthy: lengthy delays Long: The meeting felt very long.

Can I use Lengthy and Long interchangeably?

Not always. Lengthy and Long are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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