ESEN

Which one to use?Beginnernoun / verbadverb

knotvsnot

'Knot' is a fastening made by tying rope, or a unit of nautical speed; 'not' is used to make a sentence negative.

Side-by-side comparison

knot

noun / verb

Noun: a fastening made by tying together rope or string. Also a unit of speed for ships (one knot = 1.85 km/h).

She tied the ribbon into a perfect bow knot.
The ship was travelling at eighteen knots when it encountered the storm.
He felt a knot in his stomach before the presentation.

not

adverb

Adverb. Used to form negatives with verbs, adjectives, or entire phrases.

This is not the correct version of the file.
She is not available until after lunch.
It's not what you know, it's who you know.

Common mistake

Spelling error from the silent K: writing 'not' instead of 'knot' for a tied rope. The pair also famously appears in nautical puns and wordplay: 'I'm knot ready' (not ready).

Trick to remember it

'Knot' starts with a silent K, like 'know', 'knife', 'knee', and 'knight'. The K is there but silent — tied up and unable to sound, just like a knot. 'Not' without K is the simple negative.

Quick rule

Is it a tied fastening or nautical speed? 'Knot' (with a silent K). Is it a negative word? 'Not'.

Did you know?

The nautical 'knot' dates to the 17th century, when sailors threw a log tied to a knotted rope into the sea and counted how many knots passed through their hands in 30 seconds. That count gave the ship's speed in 'knots per hour' — which is why a knot is both a tied rope and a speed unit.

Practise what you learned

Exercise 1 · Pick the right one

Could you tie a _____ in the rope so the bag does not slide off the hook?

Exercise 2 · Pick the right one

Please do _____ share confidential documents outside the team.

Exercise 3 · Form the word

Frequently asked questions

When do I use "knot" and when do I use "not"?

Is it a tied fastening or nautical speed? 'Knot' (with a silent K). Is it a negative word? 'Not'.

What is the most common mistake with "knot" and "not"?

Spelling error from the silent K: writing 'not' instead of 'knot' for a tied rope. The pair also famously appears in nautical puns and wordplay: 'I'm knot ready' (not ready).

How do I remember the difference between "knot" and "not"?

'Knot' starts with a silent K, like 'know', 'knife', 'knee', and 'knight'. The K is there but silent — tied up and unable to sound, just like a knot. 'Not' without K is the simple negative.

Bryan López

Founder of SpeakUP Academy

July 29, 2026

See all word pairs Explore more confusing words

Side-by-side comparison

knot

noun / verb

Noun: a fastening made by tying together rope or string. Also a unit of speed for ships (one knot = 1.85 km/h).

She tied the ribbon into a perfect bow knot.
The ship was travelling at eighteen knots when it encountered the storm.
He felt a knot in his stomach before the presentation.

not

adverb

Adverb. Used to form negatives with verbs, adjectives, or entire phrases.

This is not the correct version of the file.
She is not available until after lunch.
It's not what you know, it's who you know.

Practise what you learned

Exercise 1 · Pick the right one

Could you tie a _____ in the rope so the bag does not slide off the hook?

Exercise 2 · Pick the right one

Please do _____ share confidential documents outside the team.

Exercise 3 · Form the word

Frequently asked questions

When do I use "knot" and when do I use "not"?

Is it a tied fastening or nautical speed? 'Knot' (with a silent K). Is it a negative word? 'Not'.

What is the most common mistake with "knot" and "not"?

Spelling error from the silent K: writing 'not' instead of 'knot' for a tied rope. The pair also famously appears in nautical puns and wordplay: 'I'm knot ready' (not ready).

How do I remember the difference between "knot" and "not"?

'Knot' starts with a silent K, like 'know', 'knife', 'knee', and 'knight'. The K is there but silent — tied up and unable to sound, just like a knot. 'Not' without K is the simple negative.