1

on

play
preposition \ˈȯn, ˈän\

Definition of on

  1. 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 tableb —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 wallc —used as a function word to indicate position in close proximity with a village on the sea stay on your opponentd —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. 2a —used as a function word to indicate a source of attachment or support on a string stand on one foot hang it on a nailb —used as a function word to indicate a source of dependence you can rely on me feeds on insects lives on a pensionc —used as a function word to indicate means of conveyance on the busd —used as a function word to indicate presence in the possession of had a knife on him

  3. 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. 4 archaic :  of

  5. 5a —used as a function word to indicate manner of doing something ; often used with the on the sly keep everything on the up-and-upb —used as a function word to indicate means or agency cut myself on a knife talk on the telephonec —used as a function word to indicate a medium of expression on stage best show on television

  6. 6a (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 drugsb —used as a function word to indicate involvement or participation on tour on the team on dutyc —used as a function word to indicate inclusion put it on the agendad —used as a function word to indicate position or status in proper relationship with a standard or objective on schedule

  7. 7a —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 dollarb —used as a function word to indicate the cause or source profited on the sale of stockc —used as a function word to indicate the focus of obligation or responsibility drinks are on the house put the blame on me

  8. 8a —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 meb —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. 9a —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 loanb —used as a function word to indicate the focus of feelings, determination, or will have pity on me keen on sports a curse on youc —used as a function word to indicate the object with respect to some misfortune or disadvantageous event the crops died on themd —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 pricee :  with respect to go light on the salt short on cash

  10. 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. 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 onb :  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. 2a :  forward or at a more advanced point in space or time went on home later onb :  in continuance or succession rambled on and so on

  3. 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.

Origin and Etymology of on

see 1on


3

on

adjective

Definition of on

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

  2. 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. 3 :  aware of something —usually used with to My boss was on to me.

  4. 4 :  intended, planned has nothing on for tonight

  5. 5 British :  talking or harping incessantly —used with about

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

  7. 7a :  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.

Origin and Etymology of on

see 1on


ON

abbreviation
variants: or

Ont

Definition of ON

  1. Ontario


1

-on

noun suffix

Definition of -on

  1. :  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. 1 :  subatomic particle nucleon

  2. 2a :  unit :  quantum photon magnetonb :  basic hereditary component cistron operon

Origin and Etymology of -on

from -on (in ion)


3

-on

noun suffix

Definition of -on

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

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

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

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

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

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

  8. 8 :  sometime during We can begin work on Monday.

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

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

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


2

on

play
adverb

Definition of on for Students

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

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

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

  4. 4 :  from one to another Pass the word on.


3

on

play
adjective

Definition of on for Students

  1. 1 :  being in operation The radio is on.

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

  3. 3 :  taking place The game is on.

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


ON

abbreviation

Definition of ON for Students

  1. Ontario


Medical Dictionary

on

play
preposition \ˈȯn, ˈän\

Medical Definition of on

  1. :  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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