Nasty

Origin unknown.

etymological hypotheses

Theories include:

Alteration of nasky ("nasty"), probably of origin, akin to Swedish naskug ("nasty, dirty"), Low German nask ("nasty"), Swedish snaskig ("dirty, messy").
Old French nastre ("bad, strange"), shortened form of villenastre ("infamous, bad"), from vilein ("villain") + -astre ("pejorative suffix"), from Latin -aster.
Dutch nestig ("dirty (literally, "like a bird's nest")")
Old High German naz = "wet"
Likely reinforced by a Scandinavian source (compare Swedish dialect naskug = "dirty, nasty").
A hardened form of an old word "neshy" = "soft".
Variant of "naughty"? See entry for aught/naught in Wikipedia & Wiktionary
Modern usage of the word "nasty" is sometimes attributed to the very popular but often derogatory 19th Century American political cartoons of Thomas Nast, but this is inconsistent with its usage long before Mr. Nast's birth in 1840.

Full definition of nasty

1651, w, Leviathan, In such condition, there is no place for Industry; because the fruit thereof is uncertain: and consequently no Culture of the Earth; no Navigation, nor use of the commodities that may be imported by Sea; no commodious Building; no Instruments of moving, and removing such things as require much force; no Knowledge of the face of the Earth; no account of Time; no Arts; no Letters; no Society; and which is worst of all, continuall feare, and danger of violent death; And the life of man, solitary, poore, nasty, brutish, and short.
2006, Marie Fontaine, The Chronicles of my Ghetto Street Volume One, p. 156:I really don't have any friends at school Mama Mia. They talk about me all the time. They say my hair's nappy and my clothes are nasty.
2013-06-01, Towards the end of poverty, But povertyâ€™s scourge is fiercest below $1.25 (the average of the 15 poorest countriesâ€™ own poverty lines, measured in 2005 dollars and adjusted for differences in purchasing power): people below that level live lives that are poor, nasty, brutish and short.

1897, Bram Stoker, Dracula:Jonathan kept staring at him, till I was afraid he would notice. I feared he might take it ill, he looked so fierce and nasty.

1838, Charles Dickens, Oliver Twist:â€˜It's a nasty trade,â€™ said Mr. Limbkins, when Gamfield had again stated his wish.

1933, Dorothy L Sayers, Murder Must Advertise:He said to Mr. Tallboy he thought the headline was a bit hot. And Mr. Tallboy said he had a nasty mind.
2009, Okera H, Be Your Priority, Not His Option, Mill City Press 2009, p. 45:We want threesomes, blowjobs, and orgies. That's just the way it is. We want the good girl who's nasty in bed.

2012, The Guardian, 3 Jun 2012:She had said: "I love the block button on Twitter. I don't know how people expect to send a nasty comment and not get blocked."

2007, The Observer, 5 Aug 2007:There was a nasty period during the First World War when the family's allegiance was called into question - not least because one of the Schroders had been made a baron by the Kaiser.

(chiefly _UK) Grave or dangerous (of an accident, illness etc.). from 19th c.

2012, James Ball, The Guardian, 2 Mar 2012:Moving into the middle ages, William the Conqueror managed to rout the English and rule the country, then see off numerous plots and assassination attempts, before his horse did for him in a nasty fall, killing him at 60.

(plural nasties)

(informal) Something nasty.Processed foods are full of aspartame and other nasties.This video game involves flying through a maze zapping various nasties.
(euphemistic, preceded by "the") Sexual intercourse.