Word origin · etymology
Descriptive English phrase with Latin-derived vocabulary.
Exact comes from Latin exactus, associated with examining or measuring; transit from transitus, passage. The phrase names a specified angular passage precisely located in time.
How we know · epistemology
Calculated angular event and declared search convention
The ephemeris, reference, target and tolerance make the instant reproducible. Exactness does not define the entire orb period or establish that a personal event must happen then.
Swiss Ephemeris: Programming Interface, position and speed ↗Astro Gold macOS: Dynamic Events ↗
Connected concepts
Browse other concepts in Timing & comparison →
These links connect subjects and terminology. They do not establish a shared historical origin.
Sources & provenance
Use the citations beside each section to distinguish a calculation convention, a historical teaching and an editorial example.