insider

noun

in·​sid·​er (ˌ)in-ˈsī-dər 

ˈin-ˌsī-

: a person recognized or accepted as a member of a group, category, or organization: such as

a

: a person who is in a position of power or has access to confidential information

b

: a person (such as an officer or director) who is in a position to have special knowledge of the affairs of or to influence the decisions of a company

Examples of insider in a Sentence

Political insiders say that she is planning to run for president.

The book gives fans an insider's view of Hollywood.

Recent Examples on the Web

From the Kentucky Derby and Formula 1’s high-octane global circuit to the Winter Olympic Games in Italy, consider this your insider’s guide to some of the most luxurious events that Black women can take up space in this year. —Essence, 2 Jan. 2026

As a spate of recent insider-trading scandals among senior Fed officials demonstrates, the institution can’t even hold its own personnel accountable. —Aaron Klein, The Atlantic, 2 Jan. 2026

Known for her outspokenness about the failures of the fashion industry and about the Israel–Hamas war, Karefa-Johnson is at once a fashion insider, who attends fashion weeks in Milan and Paris, and a frequent critic. —Rachel Tashjian, CNN Money, 2 Jan. 2026

Industry insiders and airline analysts have said the yellow-plane airline will have to make much bigger moves with this bankruptcy. —Leslie Josephs, CNBC, 2 Jan. 2026

Word History

First Known Use

1848, in the meaning defined above

Phrases Containing insider

• insider trading

Rhymes for insider

• collider
• confider
• divider
• outsider
• provider
• cider
• cyder
• eider
• glider
• hider
• rider
• schneider

Kids Definition

insider

noun

in·​sid·​er (ˈ)in-ˈsīd-ər 

: a person who is a member of a special group or organization

Legal Definition

insider

noun

in·​sid·​er

: a person who is in a position of power or has access to confidential information: as

a

: one (as an officer, director, employee, relative, or owner of more than 10% of the corporation's stock) who is in a position to have special knowledge of the affairs of or to influence the decisions of a company

b

: an individual (as a relative or an influential party) or entity (as a corporate affiliate) having a close relationship with a debtor such that transactions are not made at arm's length and are subject to closer scrutiny than the transactions of those dealing at arm's length