This is the 12182nd most frequent Polish word.
masowego
"Masowego" means "mass" or "of mass" (relating to large-scale or mass quantities).
The word 'masowego' here describes the scope or scale of 'eksportu', indicating it is conducted massively or on a large scale.
Przemysł masowego eksportu rozwija się dynamicznie.
The industry of mass export is developing dynamically.
In this context, 'masowego' modifies 'zainteresowania' to signify interest that encompasses a large group of people or masses.
Masowego zainteresowania nie wzbudził ten projekt.
This project did not arouse mass interest.
Here, 'masowego' characterizes 'wydarzenia' as being aimed at or involving a large group of participants or attendees.