Microglia wani nau'i ne na ƙananan ƙwayoyin neuroglial da aka samo a cikin kwakwalwa da kashin baya wanda ke aiki a matsayin na farko da kuma babban nau'i na kariya mai aiki a cikin tsarin juyayi na tsakiya. Suna da alhakin kawar da matattu ko lalacewa ta hanyar neurons, da kuma sauran abubuwa masu cutarwa kamar kwayoyin cuta, ƙwayoyin cuta, da guba, kuma suna da mahimmanci wajen kiyaye lafiyar kwakwalwa. Kalmar "microglia" ta fito ne daga kalmomin Helenanci "micros," ma'ana ƙanana, da "glia," ma'ana manne ko ƙwayoyin neuroglial.