The Dictionary of Obscure Sorrows are words created to explain emotions that do not have words. The author, John Koenig, uses his research in etymology to create words to describe specific emotions that have no word.

lilo
n. a friendship that can lie dormant for years only to pick right back up instantly, as if no time had passed since you last saw each other.

vellichor
n. the strange wistfulness of used bookstores, which are somehow infused with the passage of time—filled with thousands of old books you’ll never have time to read, each of which is itself locked in its own era, bound and dated and papered over like an old room the author abandoned years ago, a hidden annex littered with thoughts left just as they were on the day they were captured.

silience
n. the kind of unnoticed excellence that carries on around you every day, unremarkably—the hidden talents of friends and coworkers, the fleeting solos of subway buskers, the slapdash eloquence of anonymous users, the unseen portfolios of aspiring artists—which would be renowned as masterpieces if only they’d been appraised by the cartel of popular taste, who assume that brilliance is a rare and precious quality, accidentally overlooking buried jewels that may not be flawless but are still somehow perfect.