In Washington State, closing is considered the day that the deed is recorded into the buyer's names and the proceeds are paid to the seller. When you can take the legal possession of the property depends on the terms or conditions of the contract.
As far as possession is concerned, this can get very vague and confusing, when it really shouldn't be. Let me explain.
Legal possession can only occur when the deed is recorded and the funds disbursed. The gray area becomes, what time of day did this occur. 9 am? Noon? 2 pm? To protect your best interests, Rick would place the time of day, as well as the day of the month in which possession legally occurs right on your purchase and sales contract.
We also have a standard practice in Washington State called 'Possession + x Days' (the number of days can very, but it is typically three (3)). This means that you may have possession three days after the recording and disbursement of funds. This was designed to give the sellers a chance to move out because most people need to establish the proceeds from their home sale to purchase the next one. Once again, Rick will establish the time of the day and day of the month on your contract so there is no misunderstanding or delays.