a tough membranous area surrounding the anus in echinoderms and certain other invertebrates
periproct in American English
(ˈperəˌprɑkt)
noun
(in certain echinoids)
that part of the body surface bordering the anus
Derived forms
periproctalperiprocticperiproctous
adjective
Word origin
[1875–80; peri- + -proct ‹ Gk prōktós anus]This word is first recorded in the period 1875–80. Other words that entered Englishat around the same time include: authoritarian, cross-fertilization, knockabout, musical chairs, overdraftperi- is a prefix meaning “about” or “around” (perimeter, periscope), “enclosing” or “surrounding” (pericardium), and “near” (perigee, perihelion), appearing in loanwords from Greek (peripeteia). On this model, peri- is used in the formation of compound words (perimorph)