atac·​tic (ˌ)ā-ˈtak-tik How to pronounce atactic (audio)
: of, relating to, or being a polymer exhibiting no stereochemical regularity of structure
atactic polypropylene
compare isotactic

Word History


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

Dictionary Entries Near atactic

Cite this Entry

“Atactic.” Dictionary, Merriam-Webster, Accessed 30 Mar. 2023.

Medical Definition


atac·​tic (ˈ)ā-ˈtak-tik How to pronounce atactic (audio)
: lacking regularity or coordination
specifically : characterized by ataxia
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