This is the 11411th most frequent Russian word.
длительная
Prolonged; lasting for a long time.
Here, 'длительная' functions as an adjective describing the noun 'прогулка', indicating the duration as being extended or lengthy.
Эта длительная прогулка помогает расслабиться.
This long walk helps to relax.
The word 'длительная' describes 'командировка', emphasizing that the trip will be extended in time.
У него будет длительная командировка.
He will have a long business trip.
In this case, 'длительная' characterizes 'пауза' to indicate that the pause lasts longer than usual, imparting a sense of continuance.