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definitions

D.C.

Music. da capo.
Dictionary of Canadianisms.
Electricity. direct current.
District of Columbia.
Doctor of Chiropractic.

D & C

or D and C

noun Medicine/Medical.

a surgical method for the removal of diseased tissue or an early embryo from the lining of the uterus by means of scraping.

Origin of D & C

d(ilation) and c(urettage)
Also called dilation and curettage, dilitation and curettage.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for d.c.

D.C.

abbreviation for (in the US and Canada)

Doctor of Chiropractic
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 d.c.

abbreviation of direct current, attested from 1898.

D.C.

abbreviation of District of Columbia, apparently not widely used before 1820, but eventually it became necessary to distinguish it from the many other Washingtons in America. The city and the district (then known as Territory of Columbia) were named 1791; the territory was organized as a "district" in 1801, but the towns within it (Washington, Georgetown, Alexandria) remained separate municipalities and at one time all took D.C. The district was effectively organized as a unitary municipality in 1871.

Online Etymology Dictionary, © 2010 Douglas Harper
d.c. in Medicine

D & C

abbr.

dilation and curettage
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.