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definitions

proband

[proh-band]
noun Genetics.
  1. a patient who is the initial member of a family to come under study.

Origin of proband

1925–30; < Latin probandus, gerundive of probāre to test, probe
Also called propositus.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for proband

proband

noun
  1. another name (esp US) for propositus (def. 2)

Word Origin for proband

C20: from Latin probandus, gerundive of probāre to test
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 proband
n.

1929, from Latin probandus, gerundive of probare "to make good, esteem good; make credible, show, prove, demonstrate" (see prove).

Online Etymology Dictionary, © 2010 Douglas Harper
proband in Medicine

proband

[prō′bănd′]
n.
  1. An individual or member of a family being studied in a genetic investigation.index case propositus
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.