This interesting pair of words raises a few questions: Why does woman end with man? What does the wo mean? Does woman mean “man with a womb”?
In Old English (OE), man referred to both adult sexes and is of Germanic origin. Old Icelandic uses the word mathr in the same way, to refer to adults of both sexes, making konamathr (man) and kvennamathr (woman). In OE a female adult was wīfman (wife + man) and a male adult wǽpnedman (weaponed + man). Wife is OE meaning woman, origin unknown. “Weaponed-man” likely refers to a warrior and by extension adult males.
Following established rules for word changes, wifman morphed over the centuries to woman. The plural women was added later, likely to match the plural for man. Man itself was shortened from wǽpnedman by dropping the prefix, a common trend in most languages.