The parts surrounding the mouth of various invertebrates.
- ‘The peristome can seem quite large.’
- ‘The autozooids have small apertures and often preserve long peristomes inclined at an acute angle to the colony surface.’
- ‘Ammonites are complete, many with preserved peristomes.’
- ‘Spines and tube feet surrounding the peristome function in locomotion, burrowing, and food-gathering.’
- ‘Other mature modifications, such as change in the shape of the peristome, are also inconsistently observed in Paleozoic ammonoids.’
A fringe of small projections around the mouth of a capsule in mosses and certain fungi.
- ‘The sporophytes also develop peristomes and a spongy layer.’
Late 18th century: from modern Latin peristoma, from Greek peri- around + stoma mouth.