Noun, pl. Peyer’s patches
1. Organized lymphoid nodules which are aggregations of lymphoid tissue that are usually found in the lowest portion of the small intestine, the ileum, in humans; as such, they differentiate the ileum from the duodenum and jejunum. (wikipedia.org)
2. Any of several lymph nodes in the walls of the intestines near the junction of the ileum and colon. (wordnetweb.princeton.edu)
3. The numerous areas of lymphoid tissue in the wall of the small intestine that are involved in the development of immunity to antigens present there. (Google Dictionary)
4. Any of numerous large oval patches of closely aggregated nodules of lymphoid tissue in the walls of the small intestine especially in the ileum that partially or entirely disappear in advanced life and in typhoid fever become the seat of ulcers which may perforate the intestines. (merriam-webster.com)
Syn: aggregated lymphoid nodules, Peyer’s gland
Word origin: Named after Swiss physician and anatomist Johann Conrad Peyer.