1
a
: touching and being supported by the top surface of (something)
The book is (lying) on the table.
There is a lot of frosting on the cake.
b
: to a position that is supported by (something)
You can get on [=onto] the horse as soon as we've put the saddle on it.
I climbed out on [=onto] the roof.
c
—used to indicate the part or object by which someone or something is supported
How long can you stand on one foot?
He stood on the stool.
He was on his hands and knees looking for her earring.
2
—used to say that something is attached to something
He hung the painting on the wall.
Apples hung on the branches.
3
—used to indicate where someone or something is hit or touched
I bumped my head on a low branch.
He slapped me on the hand.
She kissed him on the cheek.
4
a
—used to indicate the surface or part where something is seen or located
There are marks on the wall.
I have a cut on my finger.
b
—used to say that something (such as jewelry) is being worn by someone
the ring on her finger
5
: near or close to (something or someone)
a village on [=by] the sea
6
—used to indicate the location or position of something or someone
Our house is on the left.
There is a garden on the side of the house.
We saw cows and chickens on the farm.
He lives on Main Street.
on page 102 in/of the book
Which side is it on?
7
—used to indicate the time when something happened or will happen
We met on July 24th.
On my way home [=while I was going home], I saw a car accident.
(formal) On the morning of July 24th, the suspect left his house at 8:15 a.m.
I would like the report on or before July 24th.
The TV station gives news every hour on the hour. [=at 6:00, 7:00, 8:00, etc.]
The project was finished on schedule/time. [=when it was supposed to be finished]
8
: immediately after (something)
What was your first reaction on hearing the news? [=when you heard the news]
You'll be required to pay on delivery of the package. [=when the package is delivered]
9
—used to indicate the subject of something
a book on [=about] North American birds
a discussion on current events
Let's reflect on [=upon] the poem for a moment.
a test on parts of speech
10
a
—used to indicate the device or instrument that is used to do something
He played a couple songs on the piano.
He cut his foot on a piece of broken glass.
b
—used to say that someone is using a telephone, computer, etc.
They talked on the phone for hours.
She was on the phone when I went to her office.
He has been on the computer all night.
c
—used to describe the device, system, etc., that is used for seeing something, hearing something, etc.
It's the best show on television.
I heard that song on the radio.
the display on the computer screen
a Web site on the Internet
I have the movie on DVD.
11
—used to indicate a source of something (such as money, food, information, or energy)
She lives on a small salary.
The family lives on welfare.
They make their living on [=off] tourism.
They profited on [=from] the sale of the house.
The animal feeds on insects.
I lived on cereal [=I ate a lot of cereal regularly] in my college years.
The machine runs on diesel fuel.
The story is based on fact.
12
—used to indicate the vehicle or animal by which someone or something is moved from one place to another
I sometimes go to work on a bus. [=I sometimes take a bus to get to work]
Have you ever ridden on a horse?
13
—used to say that you have something in your possession at a particular time
I only have $10 on me.
He had a knife on him.
14
—used to indicate the state of something
The house is on fire!
House sales are on the rise. [=are rising]
All shoes are on sale.
15
—used to indicate an activity that someone did or is now doing
She did well on the exam/test.
The band is currently on tour.
He is off/away on a trip/vacation.
She is on a diet.
The officers are on duty.
16
—used to indicate something (such as a medicine or drug) that a person or animal is using
He used to be on drugs, but he's off them now.
(informal) What (drugs) is she on?
They put the dog on antibiotics.
17
—used to indicate the person or thing that is responsible for something
The drinks are on me. [=I will pay for the drinks]
They blamed it on me. [=they said it was my fault]
18
a
—used to indicate the person or thing that something is directed toward
The deadline was creeping up on us. [=the deadline was getting closer]
an attack on religion
He is working on [=at] his skiing.
They are still working on the problem.
They made a down payment on the house.
He pulled a gun on me.
He turned his back on her and walked away.
a ban on smoking
Her eyes were on the road. [=she was watching the road]
b
—used to say that someone has been affected by something
The crops died on them.
Her husband walked out on her.
19
—used after an adjective to indicate the thing that a statement relates to
I am short on cash. [=I don't have much cash]
Opinions are divided on this issue.
(Brit) Sales are up on last year's but down on those of previous years.
20
: as stated or shown by (someone or something)
I have it on good authority [=a trustworthy person has told me] that the company will be relocating.
(Brit) On [=according to] these estimates, we'll be out of debt soon.
21
—used to indicate that someone or something is included as part of a team, list, etc.
She served on the jury/committee/board.
He is on the team.
That dish is no longer on the menu.
His name was on the list.
22
—used to say that someone or something has an advantage
She has three inches in height on me. [=she is three inches taller than I am]
The team has a 3-game lead on last year's champions.
She is very talented but has nothing on [=has no advantage over] her brother who is an even better singer.
23
chiefly US
—used to say that someone is playing or performing well
He is on his game. [=he is playing very well]
1
a
—used to indicate that something is attached to, covering, or supported by something else
Put the lid on.
I'll steady the horse while you get on.
She put on her glasses to read the letter.
Keep the tablecloth on.
b
—used to describe something that is being worn by someone
He put on his coat and went outside.
You can keep your shoes on.
What did he have on? [=what was he wearing?]
He had on a black shirt and jeans.
2
—used to indicate movement forward
The car stopped and then drove on.
We traveled on to the next town.
The boys went on home.
3
a
—used to indicate that an activity, event, or condition continues
The argument went on for weeks.
He worked on without a break.
Please read on for information about our products.
The teams played on in the snow.
She rambled on (and on) about her lazy husband.
From now on [=from this point in time forward], be sure to double-check your answers.
From here on (out), things should get easier. = From this point on, things should get easier.
b
: in an advanced state
We're far/well on with/in our project.
c
: at a more advanced time : at a later time
I'll come by to help you later on.
4
: from one person or thing to another
Pass the word/note on.
The tradition has been passed/handed on [=down] through the years.
Let's move/go on to the next point.
5
a
—used to indicate that something is operating, flowing, etc.
He switched the light on to read.
The lights came on.
Turn the water/TV on.
b
—used to indicate that something is being heated, prepared, etc.
I'll put the kettle/tea/coffee on (to boil). [=I will put the kettle/tea/coffee on the stove to make it warmer]
I've got coffee on, if you're interested.
6
: in or into a train, bus, etc.
She got on at the last station.
1
not used before a noun
: attached to or covering something
The lid is on tight.
2
not used before a noun
: performing or speaking in public
The band will be on in 10 minutes.
Mr. President, you are on in two minutes. [=you will be giving your speech in two minutes]
3
not used before a noun
: working at a job
He is on tomorrow from 6 a.m to 6 p.m.
4
a
not used before a noun
: operating or flowing
The radio/water/electricity is on.
b
: in a position that starts the flow of electricity, water, etc.
The switch is on.
The lever is in the on position.
5
not used before a noun
a
: taking place or happening
The deal/game is on.
(Brit) We do not have anything on [=planned] this weekend.
b
: doing something as planned
Are we still on for dinner tomorrow? [=are we still having dinner tomorrow, as we planned to do?]
6
not used before a noun
: being broadcast on television or radio
The show is on at 8 p.m.
The game is on tonight.
My favorite show is on.
7
not used before a noun chiefly US
—used to say that you are able to do something well at a particular time
My golf game was off yesterday, but it/I was on today. [=I played well today]
Cite this Entry
“On.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/on. Accessed 18 Apr. 2026.
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