This is the 3614th most frequent Polish word.
długa
"Long" (feminine form).
The word 'długa' is an adjective describing the noun 'noc' (night), showcasing singular feminine agreement.
To była długa noc.
It was a long night.
Here, 'długa' modifies the noun 'droga' (road), displaying singular feminine form due to the noun's characteristics.
Droga przed nami jest długa.
The road ahead is long.
In this instance, 'długa' describes 'rozmowa' (conversation), which is a singular feminine noun, adhering to proper adjective-noun agreement.