Definition from Wiktionary, the free dictionary
L-bomb (plural L-bombs)
- (idiomatic) an expression of love, usually one that provokes a significant change in a relationship
2003 March 22, Joe Kita, Guy Q: 1,305 Totally Essential Secrets You Either Know, Or You Don’t, Rodale, ISBN 1579548598, page 139:
- “Then take her on a tour of places that are special to the two of you — the bar where you had your first date, the park where you dropped the L-bomb, [...]”
- Most commonly used with drop.