The term 'OLD MERCURY' refers to a series of vehicles produced by the Ford Motor Company from 1967 to 1997. The three crossword solutions associated with this term are COUGAR (6 letters), TOPAZ (5 letters), and CAPRI (5 letters). COUGAR was a two-door coupe that was produced from 1967 to 1997, while TOPAZ was a four-door sedan that was produced from 1984 to 1994. Lastly, CAPRI was a two-door convertible that was produced from 1979 to 1986.