atactic

adjective

atac·tic (ˌ)ā-ˈtak-tik

: of, relating to, or being a polymer exhibiting no stereochemical regularity of structure

atactic polypropylene

compare isotactic

Word History

Etymology

International Scientific Vocabulary a- entry 2 + -tactic

First Known Use

1957, in the meaning defined above

Time Traveler

The first known use of atactic was in 1957

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at a cost

atactic

atactiform

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Cite this Entry

Style

“Atactic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/atactic. Accessed 4 Nov. 2025.

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Medical Definition

atactic

adjective

atac·tic (ˈ)ā-ˈtak-tik

: lacking regularity or coordination

specifically : characterized by ataxia

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