General
Admiral, Head, Leader
noun, の adjective
The big commander is the general or admiral (or head or leader). Basically, they're big stuff.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
大将が机の角に頭をぶつけて、たんこぶを作っちまったんだよ。
The admiral hit his head on the corner of the desk and got a lump.