\ˈȯn, ˈän\

Definition of on 

(Entry 1 of 7)

1a used as a function word to indicate position in contact with and supported by the top surface of the book is lying on the table

b used as a function word to indicate position in or in contact with an outer surface the fly landed on the ceilingI have a cut on my fingerpaint on the wall

c used as a function word to indicate position in close proximity with a village on the seastay on your opponent

d used as a function word to indicate the location of something on the lefton the south side of the houseon the farm

2a used as a function word to indicate a source of attachment or support on a stringstand on one foothang it on a nail

b used as a function word to indicate a source of dependence you can rely on mefeeds on insectslives on a pension

c used as a function word to indicate means of conveyance on the bus

d used as a function word to indicate presence in the possession of had a knife on him

3 used as a function word to indicate a time frame during which something takes place a parade on Sunday or an instant, action, or occurrence when something begins or is done on cueon arriving home, I found your letternews on the hourcash on delivery

4 archaic : of

5a used as a function word to indicate manner of doing something often used with the on the slykeep everything on the up-and-up

b used as a function word to indicate means or agency cut myself on a knifetalk on the telephone

c used as a function word to indicate a medium of expression on stagebest show on television

6a(1) used as a function word to indicate active involvement in a condition or status on the increaseon the lookout

(2) : regularly using or showing the effects of using on drugs

b used as a function word to indicate involvement or participation on touron the teamon duty

c used as a function word to indicate inclusion put it on the agenda

d used as a function word to indicate position or status in proper relationship with a standard or objective on schedule

7a used as a function word to indicate reason, ground, or basis (as for an action, opinion, or computation) I have it on good authorityon one conditionthe interest will be 10 cents on the dollar

b used as a function word to indicate the cause or source profited on the sale of stock

c used as a function word to indicate the focus of obligation or responsibility drinks are on the houseput the blame on me

8a used as a function word to indicate the object of collision, opposition, or hostile action bumped my head on a limban attack on religionpulled a gun on me

b used as a function word to indicate the object with respect to some disadvantage, handicap, or detriment has three inches in height on mea 3-game lead on the second-place teamthe joke's on me

9a used as a function word to indicate destination or the focus of some action, movement, or directed effort crept up on himfeast your eyes on thisworking on my skiingmade a payment on the loan

b used as a function word to indicate the focus of feelings, determination, or will have pity on mekeen on sportsa curse on you

c used as a function word to indicate the object with respect to some misfortune or disadvantageous event the crops died on them

d used as a function word to indicate the subject of study, discussion, or consideration a book on insectsreflect on that a momentagree on price

e : with respect to go light on the salt short on cash

10 used as a function word to indicate reduplication or succession in a series loss on losstrouble on trouble

on

adverb

Definition of on (Entry 2 of 7)

1a : in or into a position of contact with an upper surface especially so as to be positioned for use or operation put the plates on

b : in or into a position of being attached to or covering a surface especially : in or into the condition of being worn put his new shoes on

2a : forward or at a more advanced point in space or time went on home later on

b : in continuance or succession rambled on and so on

3 : into operation or a position permitting operation switched the light on

Definition of on (Entry 3 of 7)

1 : engaged in an activity or function (such as a dramatic role)

2a(1) : being in operation The radio is on.

(2) : placed so as to permit operation The switch is on.

b : taking place or being broadcast The game is on.

3 : aware of something usually used with to My boss was on to me.

4 : intended, planned has nothing on for tonight

5 British : talking or harping incessantly used with about

6 chiefly British : regarded as possible or feasible usually used in negative constructions

7a : engaged in or as if in a performance The comedian was always on.

b : being at a high level of performance

variants: or Ont

Definition of ON (Entry 4 of 7)

Ontario

Definition of -on (Entry 5 of 7)

: chemical compound not a ketone or other oxo compound parathion

Definition of -on (Entry 6 of 7)

1 : subatomic particle nucleon

2a : unit : quantum photon magneton

b : basic hereditary component cistron operon

Definition of -on (Entry 7 of 7)

: noble gas radon

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Examples of on in a Sentence

Preposition

There is a lot of frosting on the cake. books on sports heroes are my favorite reading matter

Adverb

We're far on with our project. I'll come by to help you later on.

Adjective

The lid is on tight. The band will be on in 10 minutes. He is on tomorrow from 6 a.m to 6 p.m.
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Recent Examples on the Web: Adverb

Wimbledon doesn’t use tiebreakers in the fifth set for men, or third set for women, so there’s nothing to prevent a match from going on and on and on — and that’s precisely what Isner and Anderson did, often thanks to one ho-hum hold after another. Howard Fendrich, BostonGlobe.com, "Kevin Anderson outlasts John Isner in second-longest match in Wimbledon history," 13 July 2018 From then on, the couple stood or walked beside each other while keeping their hands to themselves. Erica Gonzales, Harper's BAZAAR, "Meghan Markle and Prince Harry Are Back to Holding Hands at Royal Events," 5 July 2018 Where one artist might focus almost microscopically on, say, certain plants in a painting, women were universally depicted as sensual but distant. Charles Desmarais, SFChronicle.com, "‘Truth and Beauty’ at Legion of Honor: Pure visual pleasure of an idiosyncratic style," 29 June 2018 From now on, the police will usually have to get a warrant before seeking such information. Aziz Huq, Vox, "The latest Supreme Court decision is being hailed as a big victory for digital privacy. It’s not.," 22 June 2018 Snyder said from now on, the county will provide counts of homes destroyed. CBS News, "Hawaii volcano lava destroys more homes, including Big Island mayor's," 5 June 2018 As with other traditional hybrids, the gasoline engine shuts off automatically whenever the car comes to a stop, and the vehicle can start moving again on battery power alone for a bit before the engine kicks back on. G. Chambers Williams Iii, Houston Chronicle, "COMPACT," 13 July 2018 Stores shut down after unprecedented lines at malls nationwide » Build-A-Bear lines cut short on ‘Pay Your Age’ day in metro Atlanta Get your voucher. Sonja Haller, ajc, "How to get your $15 voucher after the failed Pay Your Age event at Build-a-Bear," 13 July 2018 Many are now on view as part of this PST: LA/LA show at the Autry — and in a time of political strife surrounding the issues of civil rights, this exhibition couldn’t be more timely. Carolina A. Miranda, latimes.com, "Datebook: Shots of old Route 66, dreamlike paintings and garments fashioned from paper," 12 July 2018

Recent Examples on the Web: Adjective

Right lane blocked and the end of the on ramp from Red Top Mountain Rd is blocked. Raisa Habersham, ajc, "BREAKING: 2 dead in rollover wreck in Bartow County," 9 May 2018 Saban has not promoted from within the on-field coaching staff for a coordinator job since Kirby Smart in 2008. Michael Casagrande, AL.com, "What Brian Daboll exit means for Alabama offense, the interesting QB offseason to come," 14 Jan. 2018 Jef Hodge will be on scene as caller, and regulars will provide decorations, food and a warm welcome to newcomers. Mary Colurso | Mcolurso@al.com, AL.com, "Things to do in Birmingham, Dec. 31-Jan. 6," 31 Dec. 2017 In a full-on horse trot, his Royal Highness put his hands in front of his body, holding on to invisible reins. Hilary Weaver, Vanities, "Prince William Galloped on British Television," 20 Dec. 2017 Satya Nadella, Microsoft’s CEO since 2014, got deep and personal during an on stage interview at Vanity Fair’s New Establishment Summit Tuesday morning in Los Angeles. Fortune, "Microsoft CEO Satya Nadella Says Empathy Makes You a Better Innovator," 3 Oct. 2017 But Miguel Almiron and Yamil Asas connected to send Villalba through on goal and past Joe Bendik in a game that was chippy with several yellow cards, some pushing and shoving and lots of cursing from Atlanta United’s fans. Atlanta United Fc, ajc, "Atlanta United ties Orlando City 1-1," 29 July 2017 Twenty-three engine companies and three fire crews were on scene as of 6:45 a.m. Thursday. Anthony Sorci And Cathy Locke, sacbee, "Ranch Fire 40 percent contained; Latrobe Fire near containment," 27 July 2017 Now Seattle is going it alone, considering a proposal to impose a city-only income tax of 2 percent on income over $250,000 for individuals and $500,000 for couples filing jointly. Daniel Beekman, The Seattle Times, "Podcast: is Seattle’s proposed income tax a good idea, or even legal?," 29 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'on.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of on

Preposition

before the 12th century, in the meaning defined at sense 1a

Adverb

before the 12th century, in the meaning defined at sense 1a

Adjective

circa 1541, in the meaning defined at sense 1

History and Etymology for on

Preposition

Middle English an, on, preposition & adverb, from Old English; akin to Old High German ana on, Greek ana up, on

Adverb

see on entry 1

Adjective

see on entry 1

Noun suffix (1)

International Scientific Vocabulary, alteration of -one

Noun suffix (2)

from -on (in ion)

Noun suffix (3)

New Latin, from -on (in argon)

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Learn More about on

Dictionary Entries near on

Omsk

Omura

Ōmura

on

-on

ON

Ona

Statistics for on

Look-up Popularity

Time Traveler for on

The first known use of on was before the 12th century

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More Definitions for on

English Language Learners Definition of on

 (Entry 1 of 3)

: touching and being supported by the top surface of (something)

: to a position that is supported by (something)

—used to indicate the part or object by which someone or something is supported

on

adverb

English Language Learners Definition of on (Entry 2 of 3)

—used to indicate that something is attached to, covering, or supported by something else

—used to describe something that is being worn by someone

—used to indicate movement forward

English Language Learners Definition of on (Entry 3 of 3)

: attached to or covering something

: performing or speaking in public

: working at a job

\ˈȯn, ˈän\

Kids Definition of on

 (Entry 1 of 4)

1 : in contact with and supported by Put the books on the table.

2 used to indicate means of being carried He rode on a tractor.

3 used to indicate the location of something Both bedrooms are on the top floor.

4 used to indicate the focus of a certain action He went down on his stomach.She chewed on gum.We called the police on him.

5 : against sense 4 There were shadows on the wall.

6 : near or connected with We stopped in a town on the river.

7 : to entry 1 sense 1 Mine is the first house on the left.

8 : sometime during We can begin work on Monday.

9 : in the state or process of on fire on sale

10 : about entry 2 sense 1 I'm looking for a book on minerals.

11 : by means of She likes to talk on the phone.

on

adverb

Kids Definition of on (Entry 2 of 4)

1 : into operation or a position allowing operation Turn the light on.

2 : in or into contact with a surface Put the kettle on. She has new shoes on.

3 : forward in time, space, or action We finally went on home. The argument went on for weeks.

4 : from one to another Pass the word on.

Kids Definition of on (Entry 3 of 4)

1 : being in operation The radio is on.

2 : placed so as to allow operation The switch is on.

3 : taking place The game is on.

4 : having been planned She has nothing on for tonight.

Kids Definition of ON

Ontario

\ˈȯn, ˈän \

Medical Definition of on 

: regularly using or showing the effects of using is on an ACE inhibitor to control hypertension was on drugs for two years before entering rehab

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Comments on on

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exaggeratedly or childishly emotional

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