: in an uncertain position : without assurance of relationship
used of taxa
the enigmatic fossil arthropods were placed incertae sedis among the Myriapoda

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Cite this Entry

“Incertae sedis.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/incertae%20sedis. Accessed 8 Jul. 2026.

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