guts, intestines, innards

being in something

a person who belongs to a group and knows its private information

(baseball, informal) A home run in which the ball does not leave the field of play; an inside-the-park home run.

(US, law, finance) Information obtained by or from a person in a position of trust (a director, an employee, a consultant) that affects the price of publicly traded securities.

plural of inside joke

Synonym of insider trading

(finance) The illegal buying or selling of securities of a publicly held company by a person who has privileged access to information concerning the company's financial condition or plans.

(rugby) a back whose primary job is to create space for the outside backs outside him, i.e. the scrum-half, the fly-half and the inside centre.

plural of inside address