giving the impression that something is questionable or dishonest; suspicious

it's a little sus that he seems to know exactly how to play this game

relating to or denoting a law under which a person could be arrested on suspicion of having committed an offence

the sus law

suspicion of having committed a crime

he was picked up on sus

realize or grasp (something)

he's sussed it

she sussed out right away that there was something fishy going on

knowledge or awareness of a specified kind

his lack of business suss

shrewd and wary

he is too suss a character to fall into that trap