All 4 Uses of

antecedent
in
Outliers

"After they put me through the whole interview and everything," Bickel said many years later, "I was brought to [the senior partner], who took it upon himself to tell me that for a boy of my antecedents", and you can imagine how Bickel must have paused before repeating that euphemism for his immigrant background, "I certainly had come far.†
Chpt 5

But I ought to understand how limited the possibilities of a firm like his were to hire a boy of my antecedents.†
Chpt 5 *

Mudge Rose saying no to Bickel because of his "antecedents" was like the Chicago Bulls turning down Michael Jordan because they were uncomfortable with black kids from North Carolina.†
Chpt 5

He will be Jewish, of course, and so, locked out of the old-line downtown law firms on account of his "antecedents."†
Chpt 5

Definitions:

(1) (antecedent)
something that happened previous to something else; or anything that precedes something
(2) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

More rarely and more specifically, antecedent can take on these specialized meanings:

Grammar: a word or phrase that precedes a pronoun and to which the pronoun refers. In She is the best at math in her grade, the pronoun her refers to the antecedent she.

Logic: a condition in a hypothetical proposition such as If all people are moral, then you are mortal.

Genealogy: All of someone's ancestors.

For less common examples, including one in math, see a comprehensive dictionary.