The phrasal verb 'check out' means to pay your bill so you can leave a hotel, club or private hospital: "I'd like to check out, please." It can also mean to prove something is true or correct: "Your story doesn't check out." "We went over the data and the theory seems to check out." You might use it to describe the process of examining something to ensure it is satisfactory: "Let's check out the spa area."  "Could I plug in the games console before I buy it, to check out if it's working correctly?" As a noun, 'check-out' is the part of the supermarket or the process in a shop where you pay for your goods: "Can you wait for me at the check-out?" Or the process involved in leaving a hotel or hospital: "You will receive your bill on check-out." You can hear this used in social and professional contexts.