(This is a series on Phrasal Verbs. There are hundreds of phrasal verbs and many of them have no relation to the words that form them. When you are learning a new phrasal verb, I recommend learning it as a completely new piece of vocabulary, instead of trying to make sense of the two pieces of the word.)
Sometimes one phrasal verb has two (or more) very different meanings. You need to understand both meanings to avoid any possible confusion. The phrasal verb “check out” is a very good example of this.
Check out – To pay a bill or finalize an account in a hotel, supermarket, online shopping, etc.
After you select the shoes you would like to buy, please check out in the front of the store.
Check out – To look at someone that you find attractive
Matt is always checking out all the girls at the gym.