hear it again

: a longing for something past

Example sentence:
Stewart was torn between a desire to grow up and a fond nostalgia for the days of his childhood.

Etymology:
"Nostalgia" means a sentimental yearning from some past time or condition. Speaking of the past, about how long ago do you think "nostalgia" made its first appearance in English? The earliest known appearance of "nostalgia" dates to the mid-1700s. Back then it referred to what was considered a pathological condition diagnosed by doctors, something that we would call severe homesickness. "Nostalgia" is the perfect word for such a condition. It was created by combining the Greek word "nostos," meaning "return home," and the New Latin ending "-algia," meaning "pain." Though "nostalgia" eventually dropped out of medical use, it continues to be used to mean homesickness as well as in the additional sense of a longing for the past.