undermeal

The story

1. Old English · inherited fromundernmǣl“morning, morning time; morning meal”
2. Middle English · inherited fromundermele
3. English todayundermeal

From Middle English undermele, undermel (“the early part of the afternoon, midday, noon; an afternoon meal or nap”), from Old English undernmǣl (“morning, morning time; morning meal”), equivalent to undern + meal. Compare the word for midday and the word undern.