role, roll

Role or role means an actor's part, or the part someone plays in a group or organization--perhaps even a family--
The star part is always the most difficult role.
Grandpa loved to play the role of a curmudgeon.

Roll or roll ( rhymes with role ) means to turn over--
Stop, drop and roll in case of fire.
Roll over, Fido.
Roll or roll is also a small round loaf of bread--
I would like my sandwich on a roll.
Don't forget the dinner rolls when you go to the store.
Roll or roll also means a list of the names of the members of a group, such as a school class or military unit--
Make sure you're there in time for roll call.
The teacher always carried her roll book with her.

Now that you know that, you can say--
"The stunt man's role required him to roll down a hill."

Note-- "rollover" ( one word ) is a financial term for reinvesting interest on one's account--
He allowed the interest to rollover until he had a large sum of money.
"Roll over" ( two words ) means to roll over onto the other side--
The dog will do a trick if you tell him to roll over.
"Roll over" may also mean to roll the wheels of a vehicle over something or someone--
Don't roll over the flowers with your bike.