lactides

https://doi.org/10.1351/goldbook.L03436
Cyclic
esters
derived by multiple esterification between two (usually) or more molecules of lactic acid or other hydroxy
carboxylic acids
. They are designated as dilactides, trilactides, etc. according to the number of hydroxy acid residues, e.g. a dilactide (a 1,4-dioxane-2,5-dione):
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1346 [Terms] [Paper]