The english term "man" is derived from Old English mann.
The Old English form had a default meaning of "adult male" (which was the exclusive meaning of "wer"), though it could signify a person of unspecified gender. The closely related "man" was used much as the Modern English "one" (e.g., "one reaps what one sows").
The Old English form is derived from Proto-Germanic *mannaz, "persona", which is also the etonym of German Mann "man husband and man "one" (pronoun), Old Norse maрr, and Gothic manna. According to Tacitus, the mythological progenitor of the Germanic tribes was called Mannus. The Germanic form is in turn derived from the Proto-Indo-European root *manu-s "man, person", which is also the root of the Indian name Manu, mythological progenitor of the Hindus. Linguists suspect this in turn is connected with a different PIE root, *men-, meaning "to think", which is also the source of English mean, German Minne ("love"), and the latin words from which English has borrowed mental, mind and remember.