There is a total of 6423 clues beginning with op
- Options for showing percentages
 - Options for target practice
 - Options for the expecting
 - Options for thinning
 - Options for traders
 - Options for tying neckties
 - Options in a catalog
 - Options in a primitive stress response
 - Options list
 - Options on a barbershop wall
 - Options on an IHOP table
 - Options package for a new car, and what can be found at the start of the answer to each starred clue
 - Options specialist?
 - Options strategy also known as a "buy-write"
 - Options to Cokes
 - Options when picking locks?
 - Options, metaphorically
 - Options-open adage
 - Options
 - OPTO-
 - Optoelectric device
 - OptometrÃa concern
 - Optometric comb form
 - Optometric entrepreneur
 - Optometric exams
 - Optometric object
 - Optometric solution
 - Optometrist
 - OPTOMETRIST chauffeurs poodles and Persians?
 - Optometrist Stanley who founded a store chain
 - Optometrist's application
 - Optometrist's cherished alma mater?
 - Optometrist's concern
 - Optometrist's concern
 - Optometrist's concern: Abbr
 - Optometrist's concerns
 - Optometrist's exam
 - Optometrist's favorite musical note?
 - Optometrist's field
 - Optometrist's focus
 - Optometrist's interest
 - Optometrist's offering, casually
 - Optometrist's office?
 - Optometrist's prescription
 - Optometrist's solution
 - Optometrist's specialty
 - Optometrist's stock
 - Optometrist's test
 - Optometrist's unit
 - Optometrist, at times
 - Optometrista's study
 - Optometrists do this
 - Optometrists examine them
 - Optometrists look at them
 - Optometrists' concerns
 - Optometrists' degrees
 - Optometrists' interest
 - Optometrists' patron saint?
 - Optometrists' procedures
 - Optometrist’s valentine?
 - Optometry concern
 - Optometry exam
 - Optometry product
 - Optometry school student, aptly
 - Optometry, in essence
 - OPTS
 - Opts (to)
 - Opts for
 - Opts for a more private life, or a feature of 16-, 27- and 42-Across?
 - Opts for a speedy toy dog from the pet store?
 - Opts for another hitch
 - Opts for membership
 - Opts for the pension
 - Opts not to be discharged
 - Opts not to opt
 - Opts out of
 - Opts
 - Opulence
 - Opulence
 - Opulent
 - Opulent architectural style
 - Opulent digs
 - Opulent feast, eg
 - Opulent home
 - Opulent position
 - Opulent prison?
 - Opulent residence
 - Opulent, in Oviedo
 - Opulent, in Ponce
 - Opulent
 - Opulu seaport
 - Opuntias
 - Opus
 - Opus abbr
 - Opus by Horace
 - Opus by T S Eliot
 - Opus Dei member
 - Opus ending
 - Opus finale
 - Opus for nine