c.1300, "entrance, arrival," lit. "what enters," perhaps a noun use of the late O.E. verb incuman
"come in," from in
(adv.) + cuman
"to come" (see come
). Meaning "money made through business or labor" first recorded 1601. Income tax
is from 1799, first introduced in Britain as a war tax, re-introduced 1842; authorized on a national level in U.S. in 1913. Incoming
was originally of game approaching the hunter.