What is "shysters"

Usage examples of "shysters".

Aware that crime and disease would both be on the increase, Pompey devoted some of his splendid organizational talents to diminishing crime and disease by hiring ex-gladiators to police the alleys and byways of the city, by making the College of Lictors keep an eye on the shysters and tricksters who frequented the Forum Romanum and other major marketplaces, by enlarging the swimming holes of the Trigarium, and plastering vacant walls with warning notices about good drinking water, urinating and defaecating anywhere but in the public latrines, clean hands and bad food.