Definition of yessum in English:

yessum

exclamation

US
dated, dialect
  • Used as a polite form of assent addressed to a woman.

    ‘‘You feel all right?’ she asked. ‘Yessum.’’
    • ‘That is the first time I have heard the phrase yessum mister since Little House on the Prairie all those years ago.’
    • ‘Yessum, Miss Daisy, I'll drive you to the store, yessum.’
    • ‘I won't talk about Bagger Vance… (yessum, weeza all trying ta’ fuget about Bagga Vance ‘roun these here parts!)’

Origin

Early 20th century: representing a regional pronunciation of yes ma'am.

Pronunciation

yessum

/ˈjɛsəm/