There is a total of 31390 clues beginning with on
- One of America's problems
- One of America's two
- One of American banking's Big Four, for short
- One of an "inquisitive" foursome?
- One of an "inquistive" four?
- One of an academic octet
- One of an acre's four
- One of an active trio
- One of an aggregate
- One of an air pair
- One of an American trio
- One of an amorous pair
- One of an ancient brotherhood
- One of an ancient dozen
- One of an angler's trio
- One of an animated seven
- One of an annual dozen
- One of an apocalyptic quartet
- One of an Arab people
- One of an au pair?
- One of an audience
- One of an avenging trio
- One of an eager trio
- One of an early rabbi group
- One of an early rabbinical group
- One of an edible bunch
- One of an educational trio
- One of an Egyptian 30
- One of an element's closely related atoms
- One of an Eli's musical pair
- One of an elite eatery trio
- One of an elite group
- One of an elk's pair
- One of an Elvis song pair
- One of an entertaining pair?
- One of an esoteric group
- One of an estimated quadrillion on Earth
- One of an evil fairy tale duo
- One of an evil seven
- One of an exiled group, settled in New Rochelle
- One of an express lane's 15 maximum
- One of an FDR quartet
- One of an historic seagoing trio
- One of an iamb's two
- One of an ice cream duo
- One of an ice-cream duo
- One of an identical pair
- One of an identical pair
- One of an identifical five, for short
- One of an Indian minority
- One of an infant's pair
- One of an infield quartet
- One of an inning's three
- One of an inning's three, which can follow the first word of 17-, 29-, 47- and 63-Across
- One of an inquisitive four?
- One of an inseparable group
- One of an inseparable pair
- One of an iPhone pair
- One of an iPod pair
- One of an Iraqi minority
- One of an iris's three
- One of an Israeli twelve
- One of an MLB quartet
- One of an oboe's pair
- One of an octopus's octet
- One of an old drive-in double feature, maybe
- One of an old film duo
- One of an old film trio
- One of an old threesome
- One of an orange trio
- One of an order of missionaries
- One of an Oreo's forty-eight
- One of an Oscar-winning couple
- One of an outdoor 18
- One of an umlaut's two
- One of an uplifting pair
- One of an urban fleet
- One of an ursine trio
- One of Anastasia's sisters
- One of anatomy's great vessels
- One of ancient China's Three Kingdoms
- One of ancient school of French poets
- One of ancient sect in Judea
- One of André's judges
- One of Anne Page's suitors
- One of Antarctica's seas
- One of Aphrodite's sons
- One of Apu's octuplets
- One of Apu's octuplets on "The Simpsons"
- One of Archie's loves
- One of Archie's pals
- One of Argus's array
- One of Ariel's sisters in "The Little Mermaid"
- One of Aristotle's fortes
- One of Arrowsmith's instruments
- One of Artemis's companions
- One of Arthur's guys
- One of Arthur's knights
- One of Artie's exes
- One of ascetic brotherhood in ancient Palestine