The crossword clue "merger" commonly has answers including "UNION" (5 letters), "AMALGAMATION" (12 letters), "UNIFICATION" (11 letters), "CARTEL" (6 letters), and "UNITER" (6 letters). The shortest common answer is "UNION," and the longest is "AMALGAMATION." Other synonyms used in crosswords for merger include "FUSION," "AFFILIATION," "ASSOCIATION," and "COMBINATION".