admiralo

A borrowed rank word, and it sits high in this frequency list for a reason that says more about the corpus than the language: nineteenth-century adventure novels in translation, where somebody is always commanding a fleet. You are unlikely to need it at a congress. The word is international enough to need no explanation, and it takes the ordinary noun affixes - admiralino if you need one, admiraleco for the rank itself. Note that admiri, to admire, is a separate root despite the shared opening syllables.