mesosome

[mez-uh-sohm, mes-, mee-zuh-, -suh-]
noun
  1. the anterior portion of the abdomen in arachnids.
  2. a whorled structure extending inward from the cell membrane in Gram-positive bacteria and containing enzymes for cellular respiration.

Origin of mesosome

First recorded in 1955–60; meso- + -some3
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018