What is referred to by 'a siamese dead heat'?

Based on the clue 'a shut one of these catches no flies', what is the answer? Based on the clue 'a shutout in gin rummy or pat harrington in one da...', what is the answer? Based on the clue 'a shy person at a dance or party', what is the answer? Based on the clue 'a shy teenager named charlie is the hero of the pe...', what is the answer? Based on the clue 'a siamese monarch a governess team up for this un...', what is the answer? Based on the clue 'a sibling by marriage not genetics', what is the answer? What is associated with: a sicilian separatist movement in 1945 campaigned for the island to become the 49th of these? Based on the clue 'a sick girls thirst is about to be quenched in the...', what is the answer?