quantal

https://doi.org/10.1351/goldbook.16017
Describing a condition that can be expressed only as "occurring" or "not occurring", such as death.
Source:
PAC, 2007, 79, 1153. (Glossary of terms used in toxicology, 2nd edition (IUPAC Recommendations 2007)) on page 1292 [Terms] [Paper]