censored data

https://doi.org/10.1351/goldbook.15545

Sample observations for which the complete distribution is not known.

Examples: A cohort study in which some persons cannot be followed to the predetermined end of the study ("right-censored data") or environmental assay data in which some results are less than the sample detection limit ("left-censored data").
Source:
PAC, 2007, 79, 1153. (Glossary of terms used in toxicology, 2nd edition (IUPAC Recommendations 2007)) on page 1187 [Terms] [Paper]