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inside - definition and synonyms

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90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

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adjective, adverb, preposition     inside pronunciation in American English
Inside can be used in the following ways:
as a preposition (followed by a noun): What’s inside the envelope? Inside of is sometimes used instead of inside, especially in American English: The beetles live inside of the tree.
as an adverb (without a following noun): I opened the box and looked inside.
as an adjective (always before a noun): the inside pages of a newspaper
  1. 1
    within the inner part or area of something
    1. a.
      enclosed in a container or space

      I always keep important papers locked inside my desk.

      I opened up my suitcase to show them what was inside.

      inside of:

      What’s inside of the box?

    2. b.
      used for saying that someone or something is in a room or building, especially when you are outside

      Richard was now safe inside his castle.

      There were lights on inside and I could hear voices.

      houses without running water or an inside toilet

    3. c.
      within an area or country

      Draw a triangle inside the circle.

      An F-117A Stealth aircraft crashed inside Serbia.

      Kasapis scored the final goal with a low shot from inside the penalty area.

    4. d.
      on the inner side of something

      She was standing just inside the door.

      Cassidy had one hand inside his jacket, as if reaching for something.

      inside pocket/lining (=on the inner side of a coat, case, etc.):

      Adam produced a small notebook from his inside pocket.

    5. e.
      in the inner part of something

      The photographs were on the inside pages of several Sunday newspapers.

      The melon was still green inside.

  2. 2
    moving or looking into something
    1. a.
      into a building

      Come inside, out of the rain.

      As I walked past the door, I glanced inside.

      You’re not allowed to go inside the museum without paying.

    2. b.
      into an enclosed container or empty space

      She reached inside her handbag and pulled out an envelope.

      Loretta opened the fridge and peered inside.

      inside of:

      What did he put inside of the trunk?

  3. 3
    within an organization
    1. a.
      within an organization or group

      There is a battle being fought inside the Reform Party.

      from inside:

      The rumors are coming from inside the company.

    2. b.
      [only before noun] only known by people who belong to a particular organization or group
      the inside story:

      the inside story of how a trade union destroyed itself

      inside knowledge:

      They seemed to have inside knowledge of CIA operations.

      inside information:

      The thieves clearly had inside information that allowed them to know when the building would be unguarded.

  4. 4
    in someone’s mind, but not always shown or expressed

    He was silent, but Elizabeth could sense the anger burning inside him.

    I knew how stubborn he could be once he’d gotten an idea inside his head.

  5. 5
    in your stomach
    1. a.
      already drunk or eaten

      With half a bottle of brandy inside me, I was beginning to feel unsteady.

      inside of:

      You’ll feel better once you get some dinner inside of you.

    2. b.
      used for talking about a feeling that you have in your stomach

      I suddenly felt sick inside.

  6. 6
    done in less than a particular amount of time

    All the remaining business could be completed inside half an hour.

    He swam the 200 meters just inside the European record.

    inside of:

    They can usually give you an answer inside of an hour.

  7. 7
    informal spending time in a prison

    The poor guy did three years inside for a crime he never committed.

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