What is Captain?
Captain meaning in Military terminology / glossary / dictionary is:
The most senior of the Subaltern Rank. A Captain can be a platoon leader but usually will be found as a 2IC of a company. From Latin caput meaning head, it became capitaneus in late Latin meaning chief which then spawned capitaine in French. In general, it means Chief Leader or Chief of a Company and was used to describe a head general.