Mamaw

The use of "mamaw" is used by

Country folk as "grandma"

"Mom can we go see mamaw today!" "No sweetie she died last night"

Papaw

The counter part to "mamaw"

Usually used by southerners as the word for :
"Grandpa"

Kid "mommm when can we go see papaw again?

Mother "Billy he died we aren't gonna see him again