Be lost on somebody Definition 1 of 2Pro Tip 1/3Subtlety Matters The phrase often refers to nuanced details or humor failing to register with someone. Her sarcastic tone was lost on her foreign guests. Pro Tip 2/3Cultural Sensitivity Be aware that cultural differences can cause things to be lost on people. Local idioms were completely lost on the tourists. Pro Tip 3/3Not Ignorance It's not about someone's intelligence, but about their awareness or knowledge. The reference to the local event was lost on the newcomer.