Egg

Egg \eg\ , noun;

Chicken egg (source)

Dating to the mid-14th century, the origin of egg is Old Norse egg. It replaced Middle English eye (from Old English æg) by the 16th century, but both forms were used for those 200ish years of coexistence. Both the Old English and Old Norse words derive from Proto-Germanic *ajja(m), which is probably from Proto-Indo-European *awi- ("egg").