The term 'SUIT DARK' can be solved by the crossword clue 'SPADES' (6 letters). SPADES is a card game that is part of the 'whist family' of card games, which also includes bridge and hearts. It is a trick-taking game that is usually played with four players in two partnerships. The suits in SPADES are SPADES, clubs, diamonds, and hearts, with SPADES being the highest ranking suit. Therefore, the term 'SUIT DARK' can be interpreted as referring to the highest ranking suit in the game of SPADES.