(more than) an amount of sth that is considered to be reasonable or acceptable :
He has more than his fair share of problems.
I've had my fair share of success in the past.
(more than) an amount of sth that is considered to be reasonable or acceptable :
He has more than his fair share of problems.
I've had my fair share of success in the past.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005