adjective
Common
longest
LONG-guhst
Longest (adjective) means the superlative form of "long"; extending the furthest in distance or time of all being compared. Example: “Of all the queues at the airport, ours was the longest.”
adjective
1
The superlative form of "long"; extending the furthest in distance or time of all being compared.
"It's not the longest or tallest viaduct in Britain, but the landscape upon which it sits makes for a stunning backdrop."
— Chris Howe, Top 10: Britain's most significant rail bridges: Ribblehead Viaduct (2025)
"Of all the queues at the airport, ours was the longest."
"The Nile is often cited as the longest river in the world."
"That was the longest day of my life."
How to use longest
Learner’s notesIn plain EnglishThe most long — used when comparing three or more things.
Common pairings
the longest day
longest river
by far the longest
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Word forms
- Plural
- longests
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Of all the queues at the airport, ours was the _____.
Frequently asked questions
What does “longest” mean?
The word “longest” means the superlative form of "long"; extending the furthest in distance or time of all being compared. In plain terms, the most long — used when comparing three or more things.
How do you pronounce “longest”?
“Longest” is pronounced LONG-guhst (/ˈlɔŋɡəst/ in IPA).
How do you use “longest” in a sentence?
Here is “longest” used in a sentence: “The Nile is often cited as the longest river in the world.”
What part of speech is “longest”?
“Longest” is an adjective.
Is “longest” a common word?
“Longest” is a fairly common word in modern English.
What is the difference between 'longest' and 'longer'?
'Longer' is the comparative form, used to compare two things, as in 'this road is longer than that one'. 'Longest' is the superlative, used when comparing three or more, to mark the one extending furthest in distance or time, as in 'the longest road of all'.
Why do you say 'the longest' rather than just 'longest'?
Superlatives like 'longest' normally take 'the' because they single out one item as extending the furthest of all being compared. So you say 'the longest day' or 'the longest river', with 'the' marking it as unique.
What is the difference between 'longest' and 'furthest'?
'Longest' describes what extends the most in distance or duration and often applies to measured length or time. 'Furthest' emphasises the greatest distance reached from a point. A route can be the longest in total length while a traveller goes the furthest from home.
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