This is the 9023rd most frequent Catalan word.
ferroviàries
"Ferroviàries" means "railway" or "rail-related" in English.
Here, 'ferroviàries' is an adjective describing 'línies', indicating that these are railway lines.
Les línies ferroviàries interconnecten ciutats i pobles.
The railway lines interconnect cities and towns.
In this sentence, 'ferroviàries' modifies 'infraestructures', specifying the context that the infrastructures pertain to railways.
Les infraestructures ferroviàries necessiten modernització.
The railway infrastructures need modernization.
This example uses 'ferroviàries' in its masculine form, as 'ferroviaris', to describe 'treballadors', meaning workers employed in the railway sector.