shady

adjective5

1. •
   Abounding in shades.
2. •
   (informal) Not trustworthy; disreputable.

   • He is a shady character.
3. •
   Overspread with shade; sheltered from the glare of light or sultry heat.

   • you may have rooms both for summer and winter; shady for summer, and warm for winter — 1625
4. •
   Causing shade.

   • The shady trees cover him with their shadow. — 1611
5. •
   (UK, slang) Mean, cruel.

   • They were being proper shady to him. Even if you don't like someone, locking them out, stealing their clothes and ganging up on them to take the piss is just childish. — 2006