insider

insider — noun

1. a person who belongs to a particular group or organization and therefore knows t

1.nounB2
Definition

a person who belongs to a particular group or organization and therefore knows things about it that people outside the group do not know

Example

After ten years, Noor was enough of a party insider to know the candidates.

be + enough of an insider + to-infinitive

A reporter called an insider at the hospital to ask about the new cancer treatment.

Common collocations
  • become an insider
  • political insider
  • party insider
  • real insider
  • true insider
Synonyms
  • member

    any person belonging to a group; does not imply having special knowledge

  • initiate

    someone who has been formally admitted into a group; more formal and suggests a ritual or process

  • confidant

    a person trusted with private matters; emphasizes secrecy rather than group membership

Antonyms
  • outsider

    a person who does not belong to a particular group or organization

Usage Note

Often appears in the pattern 'enough of an insider' and in compound nouns such as 'party insider' or 'Washington insider'.

Common Mistakes

She is an insider of the team.
She is an insider on the team.
use 'on' or 'in' rather than 'of' after 'insider'.

2. a person who works for a company or has a close relationship with it and has acc

2.nounB2
Definition

a person who works for a company or has a close relationship with it and has access to private financial or operational information that people outside the company cannot get

Example

Securities laws forbid company insiders from trading shares based on unpublished financial results.

forbid insiders from [gerund]

The quarterly results were leaked by an insider before the official release.

passive: leaked by an insider

Common collocations
  • company insider
  • corporate insider
  • insider trading
  • insider information
Synonyms
  • director

    a specific role on a company board; narrower in meaning

  • officer

    a corporate position; implies authority but not necessarily access to all confidential data

Antonyms
  • outsider

    a person not employed by or connected to the company

Usage Note

Frequently passive or followed by 'from' + gerund in legal contexts describing restrictions. The compound 'insider trading' refers to the illegal practice of buying or selling shares using non-public information.

Common Mistakes

Every employee is an insider.
Only employees with access to private company data are considered insiders.
not all employees have confidential information; 'insider' has a specific legal meaning.

Word family

Synonym discussion

Sense: noun/1

An 'insider' is someone who not only belongs to a group but also has access to information that outsiders lack — a party insider knows the real strategy, not just the public platform. A 'member' simply belongs; you can be a member of a gym without knowing anything the staff does not. An 'initiate' has gone through a formal process of admission, often into a secret society or exclusive tradition; the word carries ceremonial weight that 'insider' does not. A 'confidant' is trusted with personal secrets, but may not be a group member at all — you confide in a friend outside your workplace. For example: 'As a party insider, Chen knew the candidate would withdraw before the newspapers did'; 'The club has over 200 members but only a handful of real insiders'; 'She was a confidant of the CEO yet never attended board meetings.'

insider ↗member ↗initiate ↗confidant

Common collocations

Nouns

Phrases

  • from an insider
  • an insider's perspective

Prepositions

Etymology

Old EnglishEnglish

Formed in the early 1800s from the adverb 'inside' (from Old English 'innan' meaning 'within' + 'sīde' meaning 'side or border') and the agent suffix '-er' (denoting a person who does or is associated with something). The word originally referred to someone who belongs to a privileged inner circle with access to knowledge not available to the general public.