1

on

play
preposition \ ˈȯn , ˈän \

Definition of on

1 a 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 ceiling
  • I have a cut on my finger
  • paint on the wall
c used as a function word to indicate position in close proximity with
  • a village on the sea
  • stay on your opponent
d used as a function word to indicate the location of something
  • on the left
  • on the south side of the house
  • on the farm
2 a used as a function word to indicate a source of attachment or support
  • on a string
  • stand on one foot
  • hang it on a nail
b used as a function word to indicate a source of dependence
  • you can rely on me
  • feeds on insects
  • lives 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 cue
  • on arriving home, I found your letter
  • news on the hour
  • cash on delivery
4 archaic :of
5 a used as a function word to indicate manner of doing something often used with the
  • on the sly
  • keep everything on the up-and-up
b used as a function word to indicate means or agency
  • cut myself on a knife
  • talk on the telephone
c used as a function word to indicate a medium of expression
  • on stage
  • best show on television
6 a (1) used as a function word to indicate active involvement in a condition or status
  • on the increase
  • on 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 tour
  • on the team
  • on 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
7 a used as a function word to indicate reason, ground, or basis (as for an action, opinion, or computation)
  • I have it on good authority
  • on one condition
  • the 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 house
  • put the blame on me
8 a used as a function word to indicate the object of collision, opposition, or hostile action
  • bumped my head on a limb
  • an attack on religion
  • pulled 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 me
  • a 3-game lead on the second-place team
  • the joke's on me
9 a used as a function word to indicate destination or the focus of some action, movement, or directed effort
  • crept up on him
  • feast your eyes on this
  • working on my skiing
  • made a payment on the loan
b used as a function word to indicate the focus of feelings, determination, or will
  • have pity on me
  • keen on sports
  • a 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 insects
  • reflect on that a moment
  • agree 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 loss
  • trouble on trouble

Examples of on in a Sentence

  1. There is a lot of frosting on the cake.

  2. books on sports heroes are my favorite reading matter

Origin and Etymology of on

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


2

on

adverb

Definition of on

1 a :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
2 a :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

Examples of on in a Sentence

  1. We're far on with our project.

  2. I'll come by to help you later on.

Recent Examples of on from the Web

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.

Origin and Etymology of on

see 1on

on Synonyms

Synonyms
ahead, forth, forward, onward
Related Words
before, fore, frontward (or frontwards)
Near Antonyms
backward (or backwards)

3

on

adjective

Definition of on

1 :engaged in an activity or function (such as a dramatic role)
2 a (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
7 a :engaged in or as if in a performance
  • The comedian was always on.
b :being at a high level of performance

Examples of on in a Sentence

  1. The lid is on tight.

  2. The band will be on in 10 minutes.

  3. He is on tomorrow from 6 a.m to 6 p.m.

Recent Examples of on from the Web

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.

Origin and Etymology of on

see 1on


ON

abbreviation
variants: or Ont

Definition of ON

Ontario

1

-on

noun suffix

Definition of -on

:chemical compound not a ketone or other oxo compound
  • parathion

Origin and Etymology of -on

International Scientific Vocabulary, alteration of -one


2

-on

noun suffix

Definition of -on

1 :subatomic particle
  • nucleon
2 a :unit :quantum
  • photon
  • magneton
b :basic hereditary component
  • cistron
  • operon

Origin and Etymology of -on

from -on (in ion)


3

-on

noun suffix

Definition of -on

:noble gas
  • radon

Origin and Etymology of -on

New Latin, from -on (in argon)


ON Defined for English Language Learners

on

play
preposition

Definition of on for English Language Learners

  • : 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

Definition of on for English Language Learners

  • —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


on

adjective

Definition of on for English Language Learners

  • : attached to or covering something

  • : performing or speaking in public

  • : working at a job


ON Defined for Kids

1

on

play
preposition \ ˈȯn , ˈän \

Definition of on for Students

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 4
  • There were shadows on the wall.
6 :near or connected with
  • We stopped in a town on the river.
7 :1to 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 :2about 1
  • I'm looking for a book on minerals.
11 :by means of
  • She likes to talk on the phone.

2

on

adverb

Definition of on for Students

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.

3

on

adjective

Definition of on for Students

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.

ON

abbreviation

Definition of ON for Students

Ontario

Medical Dictionary

on

play
preposition \ 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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