suss

 
Pronunciation: /sʌs/
British informal

verb (susses, sussing, sussed)

[with object]
  • realize; grasp: he’s sussed it [with clause]: she sussed out right away that there was something fishy going on
  • discover the true character or nature of: I reckon I’ve got him sussed

noun

[mass noun, with adjective or noun modifier]
  • knowledge or awareness of a specified kind: his lack of business suss

adjective

  • shrewd and wary: he is too suss a character to fall into that trap

Origin:

1930s: abbreviation of suspect, suspicion