in·​ter·​nal | \in-ˈtər-nᵊl, ˈin-ˌtər-\

Definition of internal 

1 : existing or situated within the limits or surface of something: such as

a(1) : situated near the inside of the body

(2) : situated on the side toward the median plane of the body

b : of, relating to, or occurring on the inside of an organized structure (such as a club, company, or state) internal affairs

2 : relating or belonging to or existing within the mind

3 : intrinsic, inherent internal evidence of forgery in a document

4 : present or arising within an organism or one of its parts internal stimulus

5 : applied or intended for application through the stomach by being swallowed an internal remedy

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Other Words from internal

internality \ ˌin-​ˌtər-​ˈna-​lə-​tē \ noun
internally \ in-​ˈtər-​nᵊl-​ē \ adverb

Synonyms & Antonyms for internal


cerebral, inner, intellectual, interior, mental, psychological (also psychologic)



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Examples of internal in a Sentence

the internal structure of the planet a patient who is experiencing internal bleeding

Recent Examples on the Web

The court previously convicted Khmer Rouge internal security commander Kaing Guek Eav, or Comrade Duch, to life in prison for his role in running the S-21 prison camp, where thousands of prisoners were tortured and executed. James Hookway, WSJ, "U.N. Tribunal for First Time Finds Former Khmer Rouge Leaders Guilty of Genocide," 16 Nov. 2018 That includes internal combustion vehicles and equipment as well as electrical transmission systems. Scott K. Johnson, Ars Technica, "What is going on with California’s horrific fires?," 13 Nov. 2018 Symptoms usually include a sore throat and fever, followed by swelling of the internal jugular veins (which run along either side of the neck), according to GARD. Korin Miller, SELF, "A 23-Year-Old College Student Died From Lemierre Syndrome, a Rare Infection She Thought Was Tonsillitis," 6 Nov. 2018 To use: Depending upon shape and thickness, meat varies in internal temperature throughout the cut. Francine Maroukian, Popular Mechanics, "The Only Meat Thermometer Any Serious Person Needs," 29 Oct. 2018 For you, Cancer darling, this energy may feel more internal than external — especially when a full moon in Gemini on Friday, November 23, activates the area of your chart associated with the subconscious. Aliza Kelly Faragher, Allure, "What November's Cancer Horoscope Means for You," 28 Oct. 2018 Eventually, the toxins can damage nervous systems and lead to potential hemorrhaging and internal bleeding. Taylor Mead, House Beautiful, "How To ID The Different Kinds Of Mold In Your House—And Their Cause," 17 Sep. 2018 But in Season 2, Serena began trying to reform the system from within, her internal conflict growing with each new indignity suffered. Jennifer Vineyard, New York Times, "‘The Handmaid’s Tale’: Yvonne Strahovski on the Harrowing Finale and Serena’s Murky Future," 11 July 2018 Widespread violence and internal conflict destabilizes countries and regions. WSJ, "Selling American Weapons Overseas Is Risky Business," 5 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'internal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of internal

15th century, in the meaning defined at sense 1

History and Etymology for internal

Middle English internalle, from Latin internus; akin to Latin inter between

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Statistics for internal

Last Updated

19 Nov 2018

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Time Traveler for internal

The first known use of internal was in the 15th century

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English Language Learners Definition of internal

: existing or located on the inside of something

: coming from inside

: existing or occurring within your body


in·​ter·​nal | \in-ˈtər-nᵊl \

Kids Definition of internal

1 : being within something : inner The core is part of the earth's internal structure.

2 : occurring or located within the body The heart is an internal organ.

3 : existing or occurring within a country internal affairs

Other Words from internal

internally adverb


in·​ter·​nal | \in-ˈtərn-ᵊl \

Medical Definition of internal 

1 : existing or situated within the limits or surface of something: as

a : situated near the inside of the body an internal layer of abdominal muscle

b : situated on the side toward the midsagittal plane of the body the internal surface of the lung

2 : present or arising within an organism or one of its parts an internal stimulus

3 : applied or intended for application through the stomach by being swallowed an internal remedy

Other Words from internal

internally \ in-​ˈtərn-​ᵊl-​ē \ adverb

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More from Merriam-Webster on internal

Thesaurus: All synonyms and antonyms for internal

Spanish Central: Translation of internal

Nglish: Translation of internal for Spanish Speakers

Britannica English: Translation of internal for Arabic Speakers

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