Olive theory
The olive theory is a tongue-in-cheek relationship theory stating two individuals are compatible, romantically or platonically, when one party hides their enjoyment of olives so their partner who also enjoys olives can have more of them. If one individual gives their partner the olives on their plate, the relationship is balanced and a good match. The phrase saw a rise in popularity in early 2024 on TikTok, though it is mostly known for its appearance in the pilot episode of How I Met Your Mother. Marshall gives his olives to Lily because she likes them and leads her to believe he dislikes them. Later on in the show, after being caught by Barney, it is revealed Marshall does like olives but sacrifices this to make Lily happy.