"Millisecond pulsars" refers to rapidly rotating, extremely dense celestial objects known as neutron stars that emit regular pulses of radiation every few milliseconds. Full definition
The researchers ruled out other objects emitting X-rays, such as neutron stars and white dwarfs, but acknowledged that up to half of the sources they found could be fast - spinning stellar corpses called millisecond pulsars rather than black holes. (sciencenews.org)
This star's capricious behavior appears to be fueled by a nearby companion star and may give new insights into the birth of millisecond pulsars. (sciencedaily.com)
In amongst the swirling mass of stars at its heart lie many intriguing systems, including X-ray sources, variable stars, vampire stars, unexpectedly bright «normal» stars known as blue stragglers, and tiny objects known as millisecond pulsars, small dead stars that rotate astonishingly quickly. (businessinsider.com)