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1

on

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preposition \ˈȯn, ˈän\

Simple Definition of on

  • : 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of on

  1. 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. 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. 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. 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. 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. 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. 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. 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. 10 —used as a function word to indicate reduplication or succession in a series <loss on loss>

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


First Known Use: before 12th century


2

on

adverb

Simple Definition of on

  • —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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of on

  1. 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. 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. 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.



Before 12th Century

First Known Use of on

before 12th century


3

on

adjective

Simple Definition of on

  • : attached to or covering something

  • : performing or speaking in public

  • : working at a job

Source: Merriam-Webster's Learner's Dictionary

Full Definition of on

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

  2. 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. 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. 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.



Circa 1541

First Known Use of on

circa 1541


ON

abbreviation

Definition of ON

  1. Ontario



Variants of on

or

Ont


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. 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

  1. :  noble gas <radon>



Origin and Etymology of -on

New Latin, from -on (in argon)


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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