- (slang, transitive) To come to understand (a person).
- We've sussed him out — he only drinks on Fridays and only in that bar in town.
- (slang, transitive) To manage to work (something) out, to determine (something).
- We've sussed out how to open the lock.
- 2012, The Economist, Electric cars: Difference Engine: Tailpipe truths
- As far as electric cars are concerned, motorists have sussed out that they do not make particularly good financial sense, even with a $7,500 handout from the federal government.