From Longman Dictionary of Contemporary Englishon the tip of your tongueon the tip of your tonguea) if something is on the tip of your tongue, you really want to say it, but then you decide not to It was on the tip of my tongue to say, ‘I’d rather have dinner with a snake.’ b) if a word, name etc is on the tip of your tongue, you know it but cannot remember it What is her name? It’s on the tip of my tongue. Joan. Joan Simpson. That’s it! → tip
