heterocyclic

adjective

het·​ero·​cy·​clic ˌhe-tə-rō-ˈsī-klik How to pronounce heterocyclic (audio) -ˈsi- How to pronounce heterocyclic (audio)
: relating to, characterized by, or being a ring composed of atoms of more than one kind
heterocycle
ˈhe-tə-rō-ˌsī-kəl How to pronounce heterocyclic (audio)
noun
heterocyclic noun

Examples of heterocyclic in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
One group, called HAAs (heterocyclic aromatic amines), form during high-temperature reactions between substances in muscle tissue. — Emily Sohn, chicagotribune.com, 7 June 2017 Cooking meat at high temperatures or in direct contact with a flame or a hot surface can produce carcinogens, including heterocyclic aromatic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs). — Brittany Poulson, People.com, 8 July 2025

Word History

Etymology

International Scientific Vocabulary

First Known Use

1899, in the meaning defined above

Time Traveler
The first known use of heterocyclic was in 1899

Phrases Containing heterocyclic

Rhymes for heterocyclic

See All Rhymes for heterocyclic

Browse Nearby Words

Heterocotylea
heterocyclic
heterocyclic amine
See all Nearby Words

Cite this Entry

“Heterocyclic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heterocyclic. Accessed 7 Jul. 2026.

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Medical Definition

heterocyclic

1 of 2 adjective
het·​ero·​cy·​clic ˌhet-ə-rō-ˈsī-klik How to pronounce heterocyclic (audio) -ˈsik-lik How to pronounce heterocyclic (audio)
: relating to, characterized by, or being a ring composed of atoms of more than one kind
heterocyclic chemical compounds

heterocyclic

2 of 2 noun
: heterocycle
Last Updated: - Updated example sentences
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