The kanji and the word are exactly the same. That means they share meanings as well.
The reading is the on'yomi reading, which you learned. This is probably because you'll see this word attached to other words, showing the rank of that thing.
I wonder where I'll rank this year.
In terms of black garlic consumption, Koichi might be number one in Portland.
I came in first at the marathon rally, so my parents bought me a mountain bike.