nostalgia

noun
1

A longing for home or familiar surroundings; homesickness. .mw-parser-output .defdate{font-size:smaller}

"Seeing food at camp similar to his mother's cooking sent a wave of nostalgia through him."

2

A bittersweet yearning for the things of the past.

"an alumnus' feelings of nostalgia for his/her years in high school"

Source: https://en.wiktionary.org/wiki/nostalgia

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