DEPUTY

adj. subordinate, serving as an assistant (i.e. deputy sheriff)

n. representative; agent; assistant

Deputy is a rank or title, or part of a title, used in various organizations with a codified command structure. It often designates someone who is "second-in-command," and as such, may precede the name of the rank directly above it. For example, a "Deputy Master" is likely to be second-in-command to the "Master" in an organization utilizing both such ranks.
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Noun
1. someone authorized to exercise the powers of sheriff in emergencies
(synonym) deputy sheriff
(hypernym) lawman, law officer, peace officer
(derivation) substitute, deputize, deputise, step in
2. an assistant with power to act when his superior is absent
(synonym) lieutenant
(hypernym) assistant, helper, help, supporter
(hyponym) second-in-command
(derivation) substitute, deputize, deputise, step in
3. a member of the lower chamber of a legislative assembly (such as in France)
(hypernym) legislator
(classification) France, French Republic
4. a person appointed to represent or act on behalf of others
(synonym) surrogate
(hypernym) agent
(hyponym) vicegerent
(derivation) substitute, deputize, deputise, step in

(n.)
One appointed as the substitute of another, and empowered to act for him, in his name or his behalf; a substitute in office; a lieutenant; a representative; a delegate; a vicegerent; as, the deputy of a prince, of a sheriff, of a township, etc.
  

(n.)
A member of the Chamber of Deputies.
  

One authorized by an officer to exercise the office or right which the officer possesses, for and in place of the latter.

In general, ministerial officers can appoint deputies unless the office is to be exercised by the ministerial officer in person; and where the office partakes of a judicial and ministerial character, although a deputy may be made for the performance of ministerial acts, one cannot be made for the performance of a judicial act. A sheriff cannot therefore make a deputy to hold an inquisition, under a writ of inquiry, though he may appoint a deputy to serve a writ.

In general, a deputy has power to do every act which his principal might do but a deputy cannot make a deputy.

A deputy should always act in the name of his principal. The principal is liable for the deputy's acts performed by him as such, and for the neglect of the deputy. The deputy is liable himself to the person injured for his own tortious acts.
   

This entry contains material from Bouvier's Legal Dictionary, a work published in the 1850's.