• synonyms


[dahy-uh g-nohs, -nohz, dahy-uh g-nohs, -nohz]
verb (used with object), di·ag·nosed, di·ag·nos·ing.
  1. to determine the identity of (a disease, illness, etc.) by a medical examination: The doctor diagnosed the illness as influenza.
  2. to ascertain the cause or nature of (a disorder, malfunction, problem, etc.) from the symptoms: The mechanic diagnosed the trouble that caused the engine knock.
  3. to classify or determine on the basis of scientific examination.
Show More
verb (used without object), di·ag·nosed, di·ag·nos·ing.
  1. to make a diagnosis.
Show More

Origin of diagnose

First recorded in 1860–65; back formation from diagnosis
Related formsdi·ag·nos·a·ble, adjectiveun·der·di·ag·nose, verb (used with object), un·der·di·ag·nosed, un·der·di·ag·nos·ing.un·di·ag·nos·a·ble, adjectiveun·di·ag·nosed, adjectivewell-di·ag·nosed, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for diagnosable


  1. to determine or distinguish by diagnosis
  2. (tr) to examine (a person or thing), as for a disease
Show More
Derived Formsdiagnosable, adjective
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 diagnosable



1861, back-formation from diagnosis. Related: Diagnosed; diagnosing.

Show More
Online Etymology Dictionary, © 2010 Douglas Harper

diagnosable in Medicine


(dīəg-nōs′, -nōz′)
  1. To distinguish or identify a disease by diagnosis.
  2. To identify a person as having a particular disease or condition by diagnosis.
Show More
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.