O antigen

noun

: an antigen that occurs in the body of a gram-negative bacterial cell

called also somatic antigen

compare h antigen

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OA
O antigen
oat cell
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Cite this Entry

“O antigen.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/O%20antigen. Accessed 26 Jul. 2025.

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