insider

English

From inside +‎ -er.

insider (plural insiders)

A person who has special knowledge about the inner workings of a group, organization, or institution.
Antonym: outsider

Near-synonyms: initiate, old hand, habitué
- 1923 July 2, “‘Big Board’ Failures”, in Time:
  Heavy losses were sustained in Simms Petroleum, which took a greater toll from supposed "Wall Street insiders" than from the general public.
- 2007 December 19, Jonathan Clayton, “Profile: Zuma charmed wives and a nation”, in Times of London, UK:
  He is also an astute ANC insider who spent ten years on Robben Island alongside Nelson Mandela and the other “grandees” of the movement.
- 2018 July 31, Julia Carrie Wong, “What is QAnon? Explaining the bizarre rightwing conspiracy theory”, in The Guardian‎^[1]:
  In a thread called “Calm Before the Storm”, and in subsequent posts, Q established his legend as a government insider with top security clearance who knew the truth about a secret struggle for power involving Donald Trump, the “deep state”, Robert Mueller, the Clintons, pedophile rings, and other stuff.
A person who is within an enclosed space.
- 1849, Herman Melville, chapter 33, in Redburn: His First Voyage. […], 1st American edition, New York, N.Y.: Harper & Brothers, […], →OCLC:
  To the insider, the ceiling is like a small firmament twinkling with astral radiations.

person who has special knowledge

person who is within an enclosed space

Borrowed from English insider.

insider c

an insider (person with inside information)
Insidern sitter på insiderinformation
The insider has inside information