1
general::
Profit by, exploit, as in The children of celebrities often trade on their family names. [Late 1800s]
American Heritage Idioms
2
general::
Phrase(s): trade on something
to use a fact or a situation to one’s advantage. • Tom was able to trade on the fact that he had once been in the army. • John traded on his poor eyesight to get a seat closer to the stage.
McGrawhill's American Idioms And Phrasal Verbs