Yankee

a native or inhabitant of the united states.
a native or inhabitant of new england.
a native or inhabitant of a northern u.s. state, especially of one of the northeastern states that sided with the union in the american civil war.
a federal or northern soldier in the american civil war.
a word used in communications to represent the letter y.
military. the nato name for a cl-ss of soviet ballistic missile submarine, nuclear powered, with up to 16 missile launchers.
of, relating to, or characteristic of a yankee or yankees:
yankee ingenuity.
contemporary examples

it’s time for us to go christopher buckley october 27, 2009
brooklyn tabernacle choir performs the battle hymn of the republic justin green january 20, 2013
tim tebow crashes to earth as denver broncos get walloped buzz bissinger december 19, 2011
war tourism orly halpern july 19, 2012
my other mom and pop christopher buckley april 25, 2009

historical examples

the continental monthly, vol 3 no 3, march 1863 various
a prisoner of morro upton sinclair
queed henry sydnor harrison
a prisoner of morro upton sinclair
a brief history of the u. s. s. imperator, one of the two largest ships in the u. s. navy. anonymous

noun
(often derogatory) a native or inhabitant of the us; american
a native or inhabitant of new england
a native or inhabitant of the northern us, esp a northern soldier in the civil war
(communications) a code word for the letter y
(finance) a bond issued in the us by a foreign borrower
adjective
of, relating to, or characteristic of yankees

[i]t is to be noted that it is common to name a droll fellow, regarded as typical of his country, after some favorite article of food, as e[nglish] jack-pudding, g[erman] hanswurst (“jack sausage”), f[rench] jean farine (“jack flour”). [century dictionary, 1902, entry for “macaroni”]

it originally seems to have been applied insultingly to the dutch, especially freebooters, before they turned around and slapped it on the english. a less-likely theory is that it represents some southern new england algonquian language mangling of english. in english a term of contempt (1750s) before its use as a general term for “native of new england” (1765); during the american revolution it became a disparaging british word for all american native or inhabitants. shortened form yank in reference to “an american” first recorded 1778.

note: the expression “yankee, go home” reflects foreign resentment of american presence or involvement in other nations’ affairs.