nostalgia

A sentimental longing or affection for the past; homesickness.

• nostalgic/nɒˈstældʒɪk/(adj)怀旧的
• nostalgically/nɒˈstældʒɪkəli/(adv)怀旧地

• feel nostalgia
• wave of nostalgia
• nostalgic memories
• nostalgia for

1. 1.The old photographs filled her with nostalgia for her childhood. (longing for past)
2. 2.There's a growing nostalgia for the simplicity of pre-smartphone life. (yearning for earlier times)

• longing/ˈlɒŋɪŋ/— deep desire for something
• yearning/ˈjɜːnɪŋ/— intense longing
• sentimentality/ˌsɛntɪmɛnˈtæləti/— excessive emotion about the past

from Greek "nostos" (homecoming) + "algos" (pain) — the pain of longing for home