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adjective re·frac·to·ry \ri-ˈfrak-t(ə-)rē\

Simple Definition of refractory

  • medical : difficult to treat or cure

  • : difficult to control or deal with

Source: Merriam-Webster's Learner's Dictionary

Full Definition of refractory

  1. 1 :  resisting control or authority :  stubborn, unmanageable

  2. 2 a :  resistant to treatment or cure <a refractory lesion> b :  unresponsive to stimulus c :  immune, insusceptible <after recovery they were refractory to infection>

  3. 3 :  difficult to fuse, corrode, or draw out; especially :  capable of enduring high temperature

refractorily play \-t(ə-)rə-lē; ˌrē-ˌfrak-ˈtȯr-ə-lē, ri-\ adverb
refractoriness play \ri-ˈfrak-t(ə-)rē-nəs\ noun

Examples of refractory in a sentence

  1. <refractory players will be ejected from the game>

  2. <believing that rules are only for other people, he's been refractory virtually his entire life>

Did You Know?

Refractory is from the Latin word refractarius. During the 17th century, it was sometimes spelled as refractary, but that spelling, though more in keeping with its Latin parent, had fallen out of use by the century's end. Refractarius, like refractory, is the result of a slight variation in spelling. It stems from the Latin verb refragari, meaning "to oppose."

Origin of refractory

alteration of refractary, from Latin refractarius, irregular from refragari to oppose, from re- + -fragari (as in suffragari to support with one's vote)

First Known Use: 1606

Synonym Discussion of refractory

unruly, ungovernable, intractable, refractory, recalcitrant, willful, headstrong mean not submissive to government or control. unruly implies lack of discipline or incapacity for discipline and often connotes waywardness or turbulence of behavior <unruly children>. ungovernable implies either an escape from control or guidance or a state of being unsubdued and incapable of controlling oneself or being controlled by others <ungovernable rage>. intractable suggests stubborn resistance to guidance or control <intractable opponents of the hazardous-waste dump>. refractory stresses resistance to attempts to manage or to mold <special schools for refractory children>. recalcitrant suggests determined resistance to or defiance of authority <acts of sabotage by a recalcitrant populace>. willful implies an obstinate determination to have one's own way <a willful disregard for the rights of others>. headstrong suggests self-will impatient of restraint, advice, or suggestion <a headstrong young cavalry officer>.



noun re·frac·to·ry

Definition of refractory

plural refractories

  1. :  a refractory person or thing; especially :  a heat-resisting ceramic material


First Known Use of refractory


REFRACTORY Defined for Kids


adjective re·frac·to·ry \ri-ˈfrak-tə-rē\

Definition of refractory for Students

  1. 1 :  resisting control or authority :  stubborn <a refractory child>

  2. 2 :  capable of enduring very high temperatures <refractory clays>

Medical Dictionary


adjective re·frac·to·ry \ri-ˈfrak-t(ə-)rē\

Medical Definition of refractory

  1. 1:  resistant to treatment or cure <a refractory fulminant lesion> <had disease that was extremely refractory to multiple intensive therapies—Michelle L. Bennett et al>

  2. 2:  unresponsive to stimulus <the refractory period of a muscle fiber>

  3. 3:  resistant or not responding to an infectious agent :  immune <refractory to reinfection>

Seen and Heard

What made you want to look up refractory? Please tell us where you read or heard it (including the quote, if possible).


to expose to danger or risk

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