There is a total of 31380 clues beginning with on
- Only character in all seven Chronicles of Narnia books
- Only character in all seven Narnia books
- Only character mentioned in the "Star Wars" crawl
- Only character shown in the final 30 minutes of “2001
- Only character with the same name in both "Rent" and "La Bohème"
- Only chemical element whose name fits this answer's length
- Only chess move in which two pieces move on the same turn
- Only chessmen who jump other pieces: Abbr
- Only Chief Justice to have a state funeral
- Only child of Mary, Queen of Scots
- Only child's lack
- Only child, maybe
- Only children
- Only CIA director appointed by Bush
- Only city from which two NHL hockey teams relocated (both went to Canada)
- Only city on California's Catalina Island
- Only city that entirely surrounds a country
- Only Clue weapon whose token isn't metallic
- Only coach to win both NFL and AFL championships
- Only coach to win four Super Bowls
- Only color of the rainbow not seen on the LGBT pride flag
- Only common English word from the Finnish
- Only common word in the English language with the consecutive letters MPG
- Only commonly ingested rock
- Only companion
- Only continent larger than Africa
- Only country in the world without a capital city
- Only country in which Catalan is the official language
- Only country whose capital starts with "Q": Abbr
- Only country with a monochromatic flag
- Only country with a non-rectangular flag
- Only country with a nonrectangular flag
- Only country without a rectangular flag
- Only creature besides humans to farm other creatures
- Only creature that blushes
- Only crime defined in our Constitution
- Only crime defined in the Constitution
- Only daughter of Elizabeth II
- Only daughter of Joseph Stalin
- Only daughter of Queen Elizabeth II and Prince Philip
- Only deaf performer to win an Oscar
- Only deer in which both sexes have antlers
- Only defenseman in NHL history to have won the scoring title
- Only defenseman to have won the NHL scoring title
- Only defenseman to have won the NHL scoring title (1970, 1975)
- Only defenseman to lead the NHL in scoring
- Only Democrat in Bush's Cabinet
- Only digit in the ZIP code for Newton Falls, Ohio
- Only direction not in a state name
- Only Dolphin quarterback to win a Super Bowl
- Only driver to win Indy and Le Mans in the same year
- Only dwarf with a three-letter name
- Only dwarf without a beard
- Only element that starts with X
- Only English pope, with "IV"
- Only English Pope
- Only Englishman buried in Arlington
- Only Englishman named a Dr of the Church
- Only Englishman to become pope (1154)
- Only Englishman to head the Vatican
- Only European capital on both a river and an ocean
- Only even prime
- Only even prime number
- Only event in which Venezuela medaled at the 2012 Olympics
- Only ex-wife of a US president
- Only externally visible part of the central nervous system
- Only facility in the world to have hosted the Olympics, Super Bowl and Final Four
- Only fair
- Only fair, or an alternative title for this puzzle?
- Only fair
- Only female Argonaut, per some sources
- Only female attorney general
- Only female character in a classic 1926 book
- Only female Israeli prime minister
- Only female to have received jazz, pop, and classical music Grammy nominations
- Only film directed by Marlon Brando
- Only film of its series directed by William Shatner
- Only film to sweep the major categories at the Golden Raspberries
- Only Finland paid them, after World War I
- Only fish in the sea?
- Only fish?
- Only five-time Horse of the Year
- Only five-time US Horse of the Year
- Only for certain tastes
- Only form that carbohydrates take?
- Only founding member of OPEC not located in the Mideast
- Only four-letter Great Lake
- Only four-letter room in Clue
- Only four-term POTUS
- Only four-term prez
- Only freely flying mammals
- Only French-produced film to win an Oscar for Best Picture (2011)
- Only gem made by an animal
- Only gestured and moved
- Only GnR original member
- Only God can make one, according to Kilmer
- Only God can make one, according to Kilmer
- Only good part of a bad movie?
- Only graphic novel to win a Pulitzer Prize (awarded 1992)
- Only Great Lake bordering Pennsylvania