Royal Flush. A straight from a ten to an ace with all five cards of the same suit. In poker all suits are ranked equally. Straight Flush. Any straight.
Rules and variations for ranking of hands in poker games, including low type of straight flush, of a suit, is known as a Royal Flush.
A royal flush is a hand in which five cards are from the same suit and in sequential order, starting exclusively with a high ace and including a king, queen, jack. A Royal Flush @ the 2007 WSOP