This is the 10655th most frequent Russian word.
возрастном
"Возрастном" means "age-related" or "pertaining to age."
The word "возрастном" is an adjective modifying "периоде", indicating that the period is related to age.
В возрастном периоде важно уделять внимание здоровью.
In the age period, attention to health is important.
Here, "возрастном" is an adjective describing "центре", specifying that the support center is associated with age-related issues.
Она работает в возрастном центре поддержки.
She works in an age-related support center.
In this example, "возрастном" modifies "секторе", signifying a sector categorized by age.