ID this Chinese explorer?

Back when I was taking Chinese history, brief mention was made of a famous Chinese explorer (in fact, the most famous of all. I believe he is thought to have discovered America, and IIRC he sailed to the Roman Empire.) Unfortunately he never appeared in the readings, so I couldn’t get his name correctly, but I wrote down his name from lecture as comething like Ch’ou Chu Kuo. Does anyone know who this guy is? I’d like to read more about him.

-Ben

Not sure if this is the right time period but could it be Cheng Ho ?

I seem to recall that the exploits of the eunuch Cheng Ho gave us the expression “gung ho”. I have no cite for this. Am I confabulating?

Perhaps Hoei-Shin ?