Definition of plum porridge in US English:

plum porridge

noun

historical
  • A thick soup or porridge containing raisins, currants, spices, etc., often flavoured with brandy, claret, or another liquor and traditionally served at Christmas.

Origin

Late 16th century; earliest use found in John Lyly (1554–1606), writer and playwright. From plum + porridge.

Pronunciation

plum porridge

/ˌplʌm ˈpɒrɪdʒ/