proglottis (pl. proglottides) In Cestoda, one of the segments of which the animal consists. Each proglottis is essentially a reproductive sac with both male and female organs. The posterior segments, containing fertilized eggs, break off and are passed out with the host's faeces. Proglottides are not the product of metameric segmentation, but are self-contained, reproductive units (each metamere works in co-operation with all others making them all functionally interdependent).

proglottis (proh-glot-iss) n. (pl. proglottids or proglottides) one of the segments of a tapeworm. Mature segments, situated at the posterior end of the worm, each consist mainly of a branched uterus packed with eggs.