A steam ship is a steam ship or steam boat. So fancy back in their day!
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
How big is this steam ship compared to the rest in this country?
We chartered a steam boat for our trip to Singapore.
How can we finance our trip around the world by steam boat?