To become distinct or separate from what is common
To focus one's study upon a particular skill, field, topic, or genre.
To make distinct or separate due to form or function.
To narrow in scope.
To be known or notorious for some specialty.
To specify: to mention specifically.
To focus one's business upon a particular item or service.
To stay back.
To keep (a physical object that one has obtained) to oneself rather than giving it back to its owner.
To keep (information, assent etc) to oneself rather than revealing it.