Role and Roll

Writers often confuse the words role and roll.

Role

The noun role means an actor's portrayal of a character or a job or function (of a person or thing).

Examples:
  • Teddy was totally convincing in the role of Shylock.
  • What's your role onboard this aircraft?
  • The thermostat's role is to keep the temperature below 200 degrees so the casing does not melt.

Roll

The word roll has several meanings:

To move by rotating or gather by rolling.
  • Roll the hay bale down the hill.
  • Roll over a bit. You're hogging the bed.
  • Roll your sleeves up and roll me the best cigar ever.
To move on wheels.
  • The skateboarders rolled past the park attendant, and he did not say a word.
A list.
  • Please check the nominal roll to ensure we're all present.
To start.
  • Roll the cameras.
  • Roll the credits. 
A small round piece of bread (i.e., a bread roll).
  • Would you like butter on your roll?

A Quick Test

ROLL THE BALL 

The word roll usually has a circular, spherical, or cylindrical connotation. For example:
  • Roll a cigar
  • Roll the film
  • Roll away.

Let the last two letters of ball bring roll to mind.

A LIST ISN'T ROUND

The most obvious exception to this is when roll means list. In this case, let the last letter of roll remind you of list. Alternatively, think of a scroll containing a list of names.