a person, as an artist or writer, who exploits, for money, his or her creative ability or training in the production of dull, unimaginative, and trite work; one who produces banal and mediocre work in the hope of gaining commercial success in the arts: As a painter, he was little more than a hack.
2.
a professional who renounces or surrenders individual independence, integrity, belief, etc., in return for money or other reward in the performance of a task normally thought of as involving a strong personal commitment: a political hack.
3.
a writer who works on the staff of a publisher at a dull or routine task; someone who works as a literary drudge: He was one among the many hacks on Grub Street.
4.
British.
a.
a horse kept for common hire or adapted for general work, esp. ordinary riding.
b.
a saddle horse used for transportation, rather than for show, hunting, or the like.
[hak-ee] 
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