rat louse

noun

: a sucking louse (Polyplax spinulosa) that is a widely distributed parasite of rats and transmits murine typhus from rat to rat

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Cite this Entry

“Rat louse.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/rat%20louse. Accessed 3 Nov. 2025.

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