Ma'anar ƙamus na "lambar atomic 5" yana nufin lamba ta musamman da aka sanya wa sinadari na boron, wanda shine adadin protons da aka samu a cikin tsakiya na zarra na boron. Atom ɗin boron shine 5, wanda ke nufin cewa zarra na boron ya ƙunshi protons 5 a cikin tsakiya. Lambar atomic wani muhimmin abu ne na sinadari kuma yana ƙayyade matsayinsa a cikin tebur na abubuwan lokaci-lokaci.
