Oncedistinct
Oncedistinct is a neologism used in discussions of identity within temporal or context-dependent frameworks. It denotes a specific kind of distinction between two entities: they are not the same object, but they differ in exactly one context or time point, and are indistinguishable in all other relevant contexts. In temporal models, two objects a and b are oncedistinct if there exists a unique time t0 such that a and b differ with respect to a chosen distinguishing predicate P at t0, and for every other time t ≠ t0, a and b agree on all predicates under consideration. This captures a pattern of discernibility that is sharped by a single distinguishing moment, after which the two entities are treated as distinct but otherwise identical within the model.
Examples: In a dataset, two records may have identical fields across all timestamps except in one timestamp
Etymology and usage: The term combines 'once' and 'distinct'. It is not widely standardized and appears primarily
See also: Identity, Indiscernibility, Temporal logic, Distinction, Data deduplication.
References: The term is relatively new and not widely adopted; readers may encounter it in selective philosophical