Insider Meaning

/ɪnˈsaɪdɚ/
B2

Definition, CEFR level B2, pronunciation, examples, and quiz.

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nounA person who has special knowledge about the inner workings of a group, organization, or institution.

nounA person who is within an enclosed space.

The insider trading scandal put a lot of people out of business.
The politician tried to cover up the insider trading.
The situation was described by one insider as ‘absolute chaos’.
CEFR Practice Quiz
Only an ____ knew the secret code to enter the secure building.
CEFR Practice Quiz (Alternate)
The journalist received a secret tip from a company ____ about the upcoming legal merger.

Etymology tree Middle English ynneside English inside Proto-Indo-European *-yósder. Proto-Italic *-āzijos Latin -āriusnom. Latin -āriusbor. Proto-Germanic *-ārijaz Proto-West Germanic *-ārī Old English -ere Middle English -ere English -er English insider From inside + -er.

"Heavy losses were sustained in Simms Petroleum, which took a greater toll from supposed "Wall Street insiders" than from the general public." — 1923 July 2, “‘Big Board’ Failures”, in Time:
"He is also an astute ANC insider who spent ten years on Robben Island alongside Nelson Mandela and the other “grandees” of the movement." — 2007 December 19, Jonathan Clayton, “Profile: Zuma charmed wives and a nation”, in Times of London, UK:
"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." — 2018 July 31, Julia Carrie Wong, “What is QAnon? Explaining the bizarre rightwing conspiracy theory”, in The Guardian:
"That, as one of my more sceptical industry insiders put it, is because there is a reluctance to commit funds to any of these plans - and we can put the blame firmly on the fact that HS2 is eating up £7bn per year for the whole term of this parliament." — 2026 March 18, Christian Wolmar, “Wales sets example with long-term rail strategy”, in RAIL, number 1057, page 43:
"To the insider, the ceiling is like a small firmament twinkling with astral radiations." — 1849, Herman Melville, chapter 33, in Redburn: His First Voyage. […], 1st American edition, New York, N.Y.: Harper & Brothers, […], →OCLC:

Explore More B2 Vocabulary Words

CEFR Practice Quiz
Only an ____ knew the secret code to enter the secure building.
CEFR Practice Quiz (Alternate)
The journalist received a secret tip from a company ____ about the upcoming legal merger.

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