Definition of noughties:
(n) :
(chiefly UK, sometimes capitalized) The decade consisting of the last year of the previous century and the first nine years of the next: from 1900 to 1909, 2000 to 2009, etc.
(n) :
Alternative letter-case form of noughties. [(chiefly UK, sometimes capitalized) The decade consisting of the last year of the previous century and the first nine years of the next: from 1900 to 1909, 2000 to 2009, etc.]