The term '$5 Bills' refers to the five-dollar bill, which is a denomination of United States currency. The crossword solutions for this term are FINS (4 letters), ABES (4 letters), and VEES (4 letters). FINS is an abbreviation for the fin whale, which is the second largest species of whale. ABES is an abbreviation for Abraham Lincoln, who is featured on the front of the five-dollar bill. VEES is an abbreviation for the letter 'V', which is featured on the back of the five-dollar bill.