MAGNITI DOIMI (yun. magnetis, az Magnetis lithos; aynan —sangi Magnesiya—shahri qadim dar Osiyoi Khurd), masnuoti shaklashon muayyan (nalshakl, gulashakl va g.)« ki az materialhoi ferromagniti yo ferrimagnitii peshaki magnitnok kardashuda sokhta meshavand va induksiyai magnitii khudro badi qati tasiri maydoni magnitnokkunanda niz nigoh medorand.
Magniti doimi ohan, nikel va baze metallhoi digarro jazb mekunad. Magniti doimii ozod ovezon kardashuda qad-qadi meridiani magniti joy megirad, dar in hol nugi ba Shimol nigaroni Magniti doimiro qutbi shimol va nugi ba Janub nigaroni onro qutbi janubi Magniti doimi menomand. Magniti doimi chun manbai mustaqili maydoni magnitii doimi dar elektrotekhnika, radiotekhnika, avtomatika vase istifoda meshavad. Dar tekhnika jismhoi bo jarayoni elektr magnitnok kardashuda — elektromagnitho niz mamuland.