vaginal cornification

https://doi.org/10.1351/goldbook.11353

Conversion of the normal epithelium of the vagina to a keratinized squamous (flattened) epithelium.

Note: The appearance of keratinized ("cornified") epithelial cells in a vaginal smear is an indication of increased estrogen levels.
Source:
PAC, 2016, 88, 713. (Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)) on page 818 [Terms] [Paper]