Bouvier’s Dictionary of Law,1856Top State Department official Patrick Kennedy sought a “quid pro quo” with the FBI that would have allowed him to change the classification markings on Clinton’s emails.
QUID PRO QUO.
This phrase signifies verbatim, what for what. It is applied to the consideration of a contract. See Co. Litt. 47, b; 7 Mann. & Gr. 998.
Black's Law Dictionary, 1st Edition, 1891
Wex Legal DictionaryQUID PRO QUO.
What for what; something for something. Used in law for the giving one valuable thing for another. It is nothing more than the mutual consideration which passes between the parties to a contract, and which renders it valid and binding.
Also see Consideration and AgreementQuid pro quo
1) In general
Latin for "something for something." An exchange of acts or things of approximately equal value.
2) In employment law
Sexual harassment in which a boss conveys to an employee that he or she will base an employment decision, e.g. whether to hire, promote, or fire that employee, on the employee's satisfaction of a sexual demand. For example, it is quid pro quo sexual harassment for a boss to offer a raise in exchange for sex.
See, e.g. Citizens United v. Federal Election Comm'n, 130 S.Ct. 876 (2009) (generally) and Burlington Industries, Inc. v. Ellerth, 524 U.S. 742 (1998) (regarding quid pro quo sexual harassment).