River
noun
When a vocab is made up of a single kanji with no okurigana (hiragana attached to the kanji) it will usually take the same meaning as the kanji it comes from. So, from that you know that this word means river.
You're in luck - the reading you learned with the kanji is the same as the one you have to learn for this vocab!
この川はアマゾン川です。
This river is the Amazon River.
川でバーベキューしたいなぁ。
I want to BBQ by the river.
えっ。そのビキニで川に入るの?
Oh. Are you going into the river in that bikini?