Definitions
American Heritage® Dictionary of the English Language, Fourth Edition
- adj. Resembling a sketch; giving only major points or parts.
- adj. Lacking in substance or completeness; incomplete.
- adj. Slight; superficial.
Century Dictionary and Cyclopedia
- Having the form or character of a sketch; suggesting in outline rather than portraying by finished execution: as, a sketchy narrative.
- Characteristic of a sketch; slight; undetailed; unfinished.
Wiktionary
- adj. Roughly or hastily laid out; intended for later refinement.
- adj. Resembling a comedy sketch, of sketch quality.
- adj. slang Of questionable or doubtful quality.
- adj. slang, of a person Suspected of taking part in illicit or dishonorable dealings.
- adj. slang, of a person Disturbing or unnerving, often in such a way that others may suspect them of intending physical or sexual harm or harassment.
GNU Webster's 1913
- adj. Containing only an outline or rough form; being in the manner of a sketch; incomplete.
WordNet 3.0
- adj. giving only major points; lacking completeness
Etymologies
- sketch + -y (Wiktionary)
Examples
“Pretty Little Liars' new guy Caleb has been described as a "sketchy guy with a heart of gold," but after last week's episode it seems he just may be the former.”
Pretty Little Liars' Tyler Blackburn: It Becomes More Clear Who Caleb Is
“She gave him an anti-inflammatory called Deremaxx (which I'm pretty sure is the brand of condom they sell in sketchy gas station men's rooms) and told him to take it easy for a week.”
“In one particularly interesting example, we see him reconstruct a massive Roman temple, the Temple of Fortune, but in sketchy form, with "how they did it" merging with "how I'd do it.”
The Washington Post: Andrea Palladio's influential architecture at National Building Museum
“Some of the details of the proposed reforms remain sketchy, and those details are important.”
“Regulation either requires more cops, which are an expensive kind of work force, or automated systems, which are sketchy from a legal point of view.”
What Causes Traffic Jams? You. - Freakonomics Blog - NYTimes.com
“As far as details go, they remain sketchy at most.”
“The details remain sketchy as, by that time, both his mother and grandmother were dead, both having taken their secret to the grave, and Nicholson subsequently had next-to-no contact with his real father.”
“Much has been said about this critic as a peculiarly powerful teacher, but de Man's influence on academic literary and cultural criticism far exceeds the limits of an identifiable school or clique, and often manifests itself in sketchy and unacknowledged fashion within scholarly work that may not desire (or even know that it has) a filiation to de Manian rhetorical reading.”
“The details of the Henan incident remain sketchy and the number of casualties is in dispute.”
“I took the Fung Wah bus both ways - don't believe people who say the chinatown buses are "sketchy" - they were awesome.”
Lists
These user-created lists contain the word ‘sketchy’.
-
Impressionism
Words that describe the art of the impressionist era.
seascapes, landscapes, modern, impression, impressionist, contemporary, flicker, sensation, modernity, perceived, perceiving, momentary and 142 more...
-
sniglets
sniglets and neologisms | protologisms
random neologisms, compound words plus more
( randomness )bimp, darf, sketchy, blurfle, doork, elbonics, facon, fuffle, gibble, gyroped, hangle, passhole and 217 more...
-
"Queen's" English
Collection of words from Old Blighty
sorted, sketchy, mate, oi, innit, ol' chum, brilliant, wicked, arse, bloody, bollocks, wanker and 12 more...
-
Twitter faves
The new favourite words of people on Twitter.
A script searches Twitter for "X is my new favourite word" and adds it to this list.
See also:
niglets, aw, flakey, shiznit, thatch, sexy, bummers, hotty, eargasms, ratchetry, weird, fab and 599 more... -
words I love to use
kerfuffle, smarmy, sketchy, grim, wheedle, piffle, prattle, loggerheads, snarky, piddling, nix, caterwaul and 90 more...
-
madmelanie's Words
monkey, folderol, snark, snarky, flibbertigibbet, faith, asshat, pirouette, avuncular, exegesis, memento mori, verisimilitude and 379 more...
-
soph2's Words
serendipity, audacity, groak, petrichor, lethologica, loganamnosis, agnuopia, dysania, dysphagia, neologism, incredulity, harbinger and 246 more...
-
The History of Cool
Words that mean "cool" around the world and through the ages.
cool, awesome, wild, stylin', groovy, neat, nifty, swell, great, tubular, radical, bitchin' and 188 more...
-
stpeter's Words
abase, abasement, abashed, abdicate, aberrant, abeyance, abhor, abhorrent, abide, abject, ablation, abnegation and 3536 more...
-
Yet more words
hootowling, hoot owl, midday, prohibitive, shutdown, gerund, tripe, doweling, detestable, good measure, boojum, undergirding and 167 more...
-
neologisms I like
nimrod, snarky, painbow, interrobang, hoser, kooky, craptastic, preggers, asshat, brainiac, shoegaze, skanker-sore and 146 more...
-
_mark's list
Words I like!
( personal list, favorite words, randomness )psy, nanobot, success, smack, vibration, microcosmic, springgraph, marksmanship, estranged, homoerotic, flex, fiasco and 1707 more...
-
useful vocab
pysmatic, relentless, storge, preamble, oscillate, itinerary, frolic, frolicsome, abdicate, frolicking, divergent, abnegate and 312 more...
-
Favorite Words
crunk, ostentatious, shellac, smoot, thrice, somnambulant, nefarious, nostalgic, shenanigans, hooligans, oracle, torr and 142 more...
-
liarsenal's list
betwixt, perhaps, corpulent, alaska, aurora borealis, endorphin, hands, hooligan, pestilence, tarantula, fur, communique and 8 more...
-
The best slang.
Slang from all areas and time periods.
dig, square, shady, sketchy, bum, dicks, deebo, hype, shite, tarnation, dip, goddamn and 2 more...
Tweets
Looking for tweets for sketchy.

EditorMark Language Log on sketchy: http://languagelog.ldc.upenn.edu/nll/?p=2180 (via Nancy Friedman, who notes that Merriam-Webster online is alone in providing the newer meaning). Jun 7, 2010
super-herbert used to refer to a person or location of questionable reputation Mar 24, 2008