Sub-Relativistic is a ‘catch all’ term that describes speeds that are not yet quite relativistic, but are far too high to simply be titled ‘massively hypersonic.’ Sub-relativistic speed starts at 1% of the speed of light, or roughly Mach 8,810.2.
See also:
- FTL
- Hypersonic
- Massively hypersonic
- Omnipresent
- Relativistic
- Speed
- Supersonic