This is the 17214th most frequent Russian word.
стрессовое
Stressful.
Here, "стрессовое" is used as an adjective modifying "время" to describe a time period characterized by stress.
У тебя напряжённое расписание, это может быть стрессовое время.
You have a busy schedule, it can be a stressful time.
"Стрессовое" is an adjective describing "окружение," indicating an environment causing or involving stress.
Стрессовое окружение часто влияет на здоровье.
A stressful environment often affects health.
"Стрессовая" is an adjective modifying "ситуацию," signifying a scenario filled with stress.