six-o-six

noun

ˌsiks-ˌō-ˈsiks

variants or 606

: arsphenamine

Word History

Etymology

from its having been the 606th compound tested and introduced by Paul Ehrlich †1915

First Known Use

1910, in the meaning defined above

Time Traveler

The first known use of six-o-six was in 1910

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Browse Nearby Words

sixmo

six-o-six

six-pack

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Cite this Entry

Style

“Six-o-six.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/six-o-six. Accessed 29 May. 2025.

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Medical Definition

six-o-six

noun

variants or 606

ˌsik-ˌsō-ˈsiks

: arsphenamine

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