ex-box
n.— «Ex-box n. hidden container of old love souvenirs.…An ex-box holds mementos of ex-lovers. It may be a physical container (of letters, photos); an electronic folder, disk or website (of old emails, jpegs, love-blogs); or a less tangible but equally emotional place in the mind.» —“What’s the word” by John Hind Guardian (U.K.) Aug. 14, 2005. (source: Double-Tongued Dictionary)
Further reading
What if, instead of being an inanimate object, a dictionary were alive? That’s the idea behind a lavishly illustrated new children’s book called The Dictionary Story (Bookshop|Amazon) by Oliver Jeffers and Sam Winston. This is part of a...