koncertowym
Koncertowym is a grammatical form of the Polish adjective koncertowy, which means "concert-" or "related to a concert." It is not a standalone noun. The form appears when the adjective is inflected for case and number, describing nouns connected with concerts, such as plans, programs, schedules, or venues.
In particular, koncertowym is the instrumental singular masculine/neuter form of the adjective, and it is also
In ordinary usage, koncertowy is more commonly seen in its nominative masculine singular form before the noun,
Etymology and family: the form derives from the noun koncert (concert) with the adjectival suffix -owy, producing
See also: koncertowy (the base adjective), koncert (the noun), sala koncertowa, plan koncertowy, program koncertowy.