This is the 8378th most frequent Russian word.
московские
"Московские" - "Moscow" (adjective, relating to Moscow or its people).
Here, 'московские' is an adjective describing 'дороги' (roads), linking them to Moscow.
Московские дороги часто бывают оживленными.
Moscow roads are often busy.
'Московские' here characterizes 'пирожные' (pastries) as being from Moscow or typical for the region.
Я люблю московские пирожные.
I love Moscow pastries.
In this sentence, 'московские' describes 'традиции' (traditions), indicating their origin or relation to Moscow.