Lieutenant

Lieutenant is half a captain. It was also a popular given name. Examples are:
*Lieutenant Uhura
*Lieutenant Kyle,
*Lieutenant M. Landon,
*Lieutenant Leslie,
*Lieutenant C. Masters,
*Lieutenant M. McGivers.
It's a known fact that most of these officers were ensigns: no gold braid on their shoulders. Thus, the only logical conclusion allowed by cannon is that these individuals were named "Lieutenant". It was a mere fortuity that Uhura was also a Starfleet lieutenant. Further, Geordi LaForge's first name was "Lieutenant". I bet you didn't know that.