This is the 15588th most frequent Russian word.
привычному
"Accustomed" or "familiar."
In this sentence, "привычному" describes the established or usual nature of the daily routine, implying familiarity and adherence to usual habits.
Мы вернулись к привычному порядку дня.
We returned to the usual daily routine.
Here, "привычному" takes the root form to which "не" is added to denote the opposite or unfamiliar nature of the schedule.
Он не может приспособиться к непривычному распорядку.
He cannot adapt to the unusual schedule.
In this example, "привычному" describes a way of life that is familiar, characteristic of seeking stability or constancy.