resorption

https://doi.org/10.1351/goldbook.11175
  1. Removal of mineralized tissue by natural processes, as in the breakdown of bone by osteoclasts or the disappearance of a tooth.
  2. Disintegration and assimilation of an embryo or fetus through a natural process involving lysis and removal of all the products of conception by cells of the maternal immune system.
  3. In multigestational pregnancies, death of one fetus followed by absorption of its tissue by another, sometimes referred to as a "vanishing twin".
Source:
PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 800 (https://doi.org/10.1515/pac-2015-1202)