a test of 'aptitude' = an 'aptitude test' [=a test that is designed to show how easily someone will be able to learn certain skills]
Anyone who can speak five languages obviously has a great natural 'aptitude' for (learning) languages.
The new test is supposed to measure the 'aptitudes' of the students.
(..) We need that lock and chain, but Lenny Jay must have gotten rid of it. BRENNAN: Perhaps not, he's arrogant. Solely due to his aptitude for trickery, he thinks he's smarter than us. JAY: I don't see why you want to look at it. Uh, please be careful. (..)2015 TvShow: Bones Title: The Promise in the Palace Season: 11 Episode 7