FACT FIRST · ANALOGY SECOND
PM2.5
Factual definition
Airborne particles with an aerodynamic diameter of 2.5 micrometres or smaller. Exposure is associated with health risks, with effects depending on concentration and duration.
SATIRICAL ANALOGY — NOT A DEFINITION
The tiny particle category that makes “I can’t see it” a weak measurement strategy.
Related entries in the source book
These are reading links, not claims that the guide entry defines this term.