fontanelle

https://doi.org/10.1351/goldbook.10734
Any of several soft spots in specific locations on the skull of the newborn where the bones have not yet fused and the brain is covered by skin and a tough membrane.
See also: cranial suture
Source:
PAC, 2016, 88, 713. (Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)) on page 757 [Terms] [Paper]