The book is named Outliers because it refers to the type of people described in the book. An outlier is defined as "a person or thing situated away or detached from the main body or system" (dictionary.com). The people described in this book are unusually successful, or seemingly gifted in some other way. This makes them different which gives them the title of an outlier. The title, "Outliers" acts as a collective name for every person who is different.