1580s, "to watch, guard, or keep order; to govern," from French policer, from police (see police (n.)). The original sense is obsolete. The meaning "to control or keep order in by means of police" is from 1837; figurative use by 1885. Related: Policed; policing.
1530s, "the regulation and control of a community" (similar in sense to policy (n.1)); from Middle French police "organized government, civil administration" (late 15c.), from Latin politia "civil administration," from Greek polis "city" (see polis).
Until mid-19c. used in England for "civil administration;" application to "administration of public order, law-enforcement in a community" (1716) is from French (late 17c.), and originally in English referred to France or other foreign nations.
The sense of "an organized civil force for maintaining order, preventing and detecting crime, etc." is by 1800; the first force so-named in England was the Marine Police, set up 1798 to protect merchandise at the Port of London. Meaning "body of officers entrusted with the duty of enforcing laws, detecting crime, etc." is from 1810.
In its most common acceptation, the police signifies the administration of the municipal laws and regulations of a city or incorporated town or borough by a corps of administrative or executive officers, with the necessary magistrates for the immediate use of force in compelling obedience and punishing violation of the laws, as distinguished from judicial remedies by action, etc. The primary object of the police system is the prevention of crime and the pursuit of offenders; but it is also subservient to other purposes, such as the suppression of mendicancy, the preservation of order, the removal of obstructions and nuisances, and the enforcing of those local and general laws which relate to the public health, order, safety, and comfort. [Century Dictionary, 1895]
In constitutional law, police power is the power of a government to limit civil liberties and exercise restraint and compulsion over private rights, especially to advance or protect the public welfare. Police state "state regulated by means of national police" first recorded 1865, with reference to Austria. Police action in the international sense of "military intervention short of war, ostensibly to correct lawlessness" is from 1933. Police officer is attested from 1794, American English. Police station is from 1817. Police dog is by 1908.
c. 1300, "head, leader, captain; the principal or most important part of anything;" from Old French chief "leader, ruler, head" of something, "capital city" (10c., Modern French chef), from Vulgar Latin *capum, from Latin caput "head," also "leader, chief person; summit; capital city" (from PIE root *kaput- "head").
The meaning "head of a clan" is attested from 1570s; it was later extended to headmen of Native American tribes (by 1713; William Penn, 1680s, called them kings). Commander-in-chief is attested from 1660s.
c. 1300, "highest in rank or power; most important or prominent; supreme, best, placed above the rest," from Old French chief "chief, principal, first" (10c., Modern French chef), from Vulgar Latin *capum (source also of Spanish and Portuguese cabo, Italian capo, Provençal cap), from Latin caput "head," also "leader, guide, chief person; summit; capital city" (from PIE root *kaput- "head").
c. 1200, "chief household officer;" c. 1300, "justice of the peace," from Old French conestable (12c., Modern French connétable), "steward, governor," principal officer of the Frankish king's household, from Medieval Latin conestabulus, from Late Latin comes stabuli, literally "count of the stable" (established by Theodosian Code, c. 438 C.E.), hence, "chief groom."
For first element, see count (n.1). Second element is from Latin stabulum "stable, standing place" (see stable (n.)). Probably the whole is a loan-translation of a Germanic word. Compare marshal (n.).
Meaning "an officer chosen to serve minor legal process" is from c. 1600, transferred to "police officer" by 1836. French reborrowed constable 19c. as "English police."
1952, contraction of international police (in full, The International Criminal Police Commission), founded 1923 with headquarters in Paris.
Nazi secret state police, 1934, from German Gestapo, contracted from "Geheime Staats-polizei," literally "secret state police," set up by Hermann Göring in Prussia in 1933, extended to all Germany in January 1934.
also d.o.a., 1929, police slang abbreviation of dead on arrival.