This is the 1036th most frequent Dutch word.
zaterdag
Saturday.
The word 'zaterdag' is used here as a specific day of the week, within a temporal prepositional phrase indicating a habitual action.
Ik ga op zaterdag altijd naar de markt.
I always go to the market on Saturday.
In this sentence, 'zaterdag' serves to situate the indicative statement about the weather in the past on a specific day of the week.
Zaterdag was het weer prachtig.
Saturday the weather was beautiful.
Here, 'zaterdag' denotes a specific upcoming day of the week, paired with 'aanstaande' to clearly indicate the future occurrence.