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definitions

operative

[op-er-uh-tiv, op-ruh-tiv, op-uh-rey-tiv]
noun
  1. a person engaged, employed, or skilled in some branch of work, especially productive or industrial work; worker.
  2. a detective.
  3. a secret agent; spy.
adjective
  1. operating, or exerting force, power, or influence.
  2. having force; being in effect or operation: laws operative in this city.
  3. effective or efficacious.
  4. engaged in, concerned with, or pertaining to work or productive activity.
  5. significant; key: The operative word in that sentence is “sometimes.”
  6. Medicine/Medical. concerned with, involving, or pertaining to surgical operations.

Origin of operative

1590–1600; < Middle French operatif < Latin operāt(us) (see operate) + Middle French -if -ive
Related formsop·er·a·tive·ly, adverbop·er·a·tive·ness, op·er·a·tiv·i·ty [op-er-uh-tiv-i-tee] /ˌɒp ər əˈtɪv ɪ ti/, nounin·ter·op·er·a·tive, noun, adjectivenon·op·er·a·tive, adjectiveun·op·er·a·tive, adjective

Synonyms for operative

1. workman, factory hand. 2. investigator, agent. 6. effectual, serviceable.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for operativity

operative

adjective
  1. in force, effect, or operation
  2. exerting force or influence
  3. producing a desired effect; significantthe operative word
  4. of or relating to a surgical procedure
noun
  1. a worker, esp one with a special skill
  2. US a private detective
Derived Formsoperatively, adverboperativeness or operativity, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for operativity

operative

n.

"worker, operator," 1809, from operative (adj.); sense of "secret agent, spy" is first attested 1930, probably from its use by the Pinkerton Detective Agency as a title for their private detectives (1905).

operative

adj.

"producing the intended effect," early 15c., from Old French operatif (14c.) or directly from Late Latin operativus "creative, formative," from operat-, past participle stem of operari (see operation). Weakened sense of "significant, important" is from 1955.

Online Etymology Dictionary, © 2010 Douglas Harper
operativity in Medicine

operative

[ŏp′ər-ə-tĭv, -ə-rā′tĭv, ŏp′rə-]
adj.
  1. Of, relating to, or resulting from a surgical operation.
  2. Functioning effectively; efficient.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.