We don't have synonyms for show time yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are slow time, showtime and short time.
(n) :
(aviation, travel) The time prior to the departure of a scheduled aircraft in which the passenger service representatives at an airport terminal may begin the roll call for assigning seats.
(n) :
Alternative form of showtime. [The time at which an entertainment event is set to begin.]
(n) :
(aviation, travel) The time prior to the departure of a scheduled aircraft in which the passenger service representatives at an airport terminal may begin the roll call for assigning seats.
(n) :
Alternative form of showtime. [The time at which an entertainment event is set to begin.]